Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 34
Filtrar
Mais filtros











Base de dados
Intervalo de ano de publicação
1.
Biochem Biophys Res Commun ; 556: 192-198, 2021 06 04.
Artigo em Inglês | MEDLINE | ID: mdl-33845309

RESUMO

Helicobacter pylori (H. pylori) infection mainly causes gastroduodenal diseases, including chronic gastritis, peptic ulcer disease and gastric cancer. In recent years, several studies have demonstrated that infection with H. pylori, especially strains harboring the virulence factor CagA (cytotoxin-associated gene A), contribute to the development of non-gastric systemic diseases, including hypercholesterolemia and atherosclerotic cardiovascular diseases. However, mechanisms underlying this association has not been defined. In this study, we carried out a large-scale genetic screen using Drosophila and identified a novel CagA target low-density lipoprotein receptor (LDLR), which aids in the clearance of circulating LDL. We showed that CagA physically interacted with LDLR via its carboxy-terminal region and inhibited LDLR-mediated LDL uptake into cells. Since deficiency of LDLR-mediated LDL uptake has been known to increase plasma LDL and accelerate atherosclerosis, our findings may provide a novel mechanism for the association between infection with CagA-positive H. pylori and hypercholesterolemia leading to atherosclerotic cardiovascular diseases.


Assuntos
Antígenos de Bactérias/metabolismo , Proteínas de Bactérias/metabolismo , Helicobacter pylori/metabolismo , Helicobacter pylori/patogenicidade , Lipoproteínas LDL/metabolismo , Receptores de LDL/metabolismo , Fatores de Virulência/metabolismo , Animais , Animais Geneticamente Modificados , Aterosclerose/microbiologia , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/genética , Drosophila melanogaster/metabolismo , Olho/metabolismo , Feminino , Humanos , Hipercolesterolemia/microbiologia , Lipoproteínas LDL/sangue , Masculino , Ligação Proteica
2.
Surg Today ; 51(8): 1410-1413, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33638697

RESUMO

BACKGROUND AND PURPOSE: To describe the procedure for a left-side approach to the superior mesenteric artery (SMA) during pancreaticoduodenectomy (PD) in a cadaveric study. OPERATIVE PROCEDURE: After dividing the upper jejunum, the jejunal artery (JA) is followed to its origin. At the cranial side of the JA, the mesojejunum to be dissected is detached from the ventral to the dorsal side and from the peripheral to the origin side of the SMA. The inferior pancreatoduodenal artery (IPDA), which is usually the common trunk of the IPDA and the first JA, is able to be visualized at the cranio-dorsal side of the origin of the JA. After cutting the IPDA, the mesojejunum can be detached from the SMA from the dorsal aspect to the right side. Subsequently, the pancreas head is dissected easily from the right aspect of the SMA. CONCLUSION: This left-side approach to the SMA may become a standard procedure.


Assuntos
Artéria Mesentérica Superior/cirurgia , Neoplasias Pancreáticas/cirurgia , Pancreaticoduodenectomia/educação , Pancreaticoduodenectomia/métodos , Idoso , Cadáver , Duodeno/irrigação sanguínea , Humanos , Jejuno/irrigação sanguínea , Masculino , Pâncreas/irrigação sanguínea , Resultado do Tratamento
3.
Cell Tissue Res ; 383(3): 1191-1202, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33242172

RESUMO

Prosaposin (PSAP) has two forms: a precursor and a secreted form. The secreted form has neurotrophic, myelinotrophic, and myotrophic properties. The precursor form is a precursor protein of saposins A-D. Although the distribution of PSAP in male reproductive organs is well known, its distribution in female reproductive organs, especially in the oviduct, is unclear. Immunoblots and immunohistochemistry of oviducts showed that oviductal tissues contain PSAP proteins, and a significant increase in PSAP was observed in the estrus-metestrus phase compared to the diestrus-proestrus phase in the ampulla. To identify PSAP trafficking in cells, double-immunostaining was performed with antibodies against PSAP in combination with sortilin, mannose 6 phosphate receptor (M6PR), or low-density lipoprotein receptor-related protein 1 (LRP1). PSAP and sortilin double-positive reactions were observed near the nuclei, as well as in the apical portion of microvillous epithelial cells, whereas these reactions were only observed near the nuclei of ciliated epithelial cells. PSAP and M6PR double-positive reactions were observed near the nuclei of microvillous and ciliated epithelial cells. PSAP and M6PR double-positive reactions were also observed in the apical portion of microvillous epithelial cells. PSAP and LRP1 double-positive reactions were observed in the plasma membrane and apical portion of both microvillous and ciliated epithelial cells. Immunoelectron staining revealed PSAP immunoreactive small vesicles with exocytotic features at the apical portion of microvillous epithelial cells. These findings suggest that PSAP is present in the oviductal epithelium and has a pivotal role during pregnancy in providing an optimal environment for gametes and/or sperm in the ampulla.


Assuntos
Células Epiteliais , Ciclo Estral/metabolismo , Tubas Uterinas , Receptor IGF Tipo 2/metabolismo , Saposinas/metabolismo , Animais , Membrana Celular/metabolismo , Células Epiteliais/citologia , Células Epiteliais/metabolismo , Tubas Uterinas/citologia , Tubas Uterinas/metabolismo , Feminino , Gravidez , Ratos , Ratos Wistar
4.
ChemMedChem ; 16(6): 955-958, 2021 03 18.
Artigo em Inglês | MEDLINE | ID: mdl-33289306

RESUMO

Discoidin domain receptor 1 (DDR1) inhibitors with a desired pharmacophore were designed using deep generative models (DGMs). DDR1 is a receptor tyrosine kinase activated by matrix collagens and implicated in diseases such as cancer, fibrosis and hypoxia. Herein we describe the synthesis and inhibitory activity of compounds generated from DGMs. Three compounds were found to have sub-micromolar inhibitory activity. The most potent of which, compound 3 (N-(4-chloro-3-((pyridin-3-yloxy)methyl)phenyl)-3-(trifluoromethyl)benzamide), had an IC50 value of 92.5 nM. Furthermore, these compounds were predicted to interact with DDR1, which have a desired pharmacophore derived from a known DDR1 inhibitor. The results of synthesis and experiments indicated that our de novo design strategy is practical for hit identification and scaffold hopping.


Assuntos
Benzamidas/farmacologia , Receptor com Domínio Discoidina 1/antagonistas & inibidores , Desenho de Fármacos , Inibidores de Proteínas Quinases/farmacologia , Benzamidas/síntese química , Benzamidas/química , Receptor com Domínio Discoidina 1/metabolismo , Relação Dose-Resposta a Droga , Humanos , Modelos Moleculares , Estrutura Molecular , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/química , Relação Estrutura-Atividade
6.
PLoS One ; 15(12): e0241315, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33259479

RESUMO

Neurotrophic factor prosaposin (PS) is a precursor for saposins A, B, C, and D, which are activators for specific sphingolipid hydrolases in lysosomes. Both saposins and PS are widely contained in various tissues. The brain, skeletal muscle, and heart cells predominantly contain unprocessed PS rather than saposins. PS and PS-derived peptides stimulate neuritogenesis and increase choline acetyltransferase activity in neuroblastoma cells and prevent programmed cell death in neurons. We previously detected increases in PS immunoactivity and its mRNA in the rat facial nucleus following facial nerve transection. PS mRNA expression increased not only in facial motoneurons, but also in microglia during facial nerve regeneration. In the present study, we examined the changes in immunoreactivity of the PS receptors GPR37 and GPR37L1 in the rat facial nucleus following facial nerve transection. Following facial nerve transection, many small Iba1- and glial fibrillary acidic protein (GFAP)-positive cells with strong GPR37L1 immunoreactivity, including microglia and astrocytes, were observed predominately on the operated side. These results indicate that GPR37 mainly works in neurons, whereas GPR37L1 is predominant in microglia or astrocytes, and suggest that increased PS in damaged neurons stimulates microglia or astrocytes via PS receptor GPR37L1 to produce neurotrophic factors for neuronal recovery.


Assuntos
Nervo Facial/metabolismo , Regeneração Nervosa/genética , Proteínas do Tecido Nervoso/genética , Receptores Acoplados a Proteínas G/genética , Saposinas/genética , Animais , Astrócitos/metabolismo , Astrócitos/patologia , Nervo Facial/cirurgia , Núcleo do Nervo Facial/metabolismo , Núcleo do Nervo Facial/patologia , Regulação da Expressão Gênica/genética , Humanos , Microglia/metabolismo , Microglia/patologia , Neurônios Motores/metabolismo , Neurônios Motores/patologia , RNA Mensageiro/genética , Ratos
7.
Dis Colon Rectum ; 62(10): 1238-1247, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31490833

RESUMO

BACKGROUND: Deep anatomic knowledge of the male anterior anorectum is important to avoid urethral injury and rectal perforation in intersphincteric resection or abdominoperineal resection for very low rectal cancer. However, its structure is difficult to understand, because the anorectum, muscles, and urogenital organs are complicatedly and 3-dimensionally arranged. OBJECTIVE: The purpose of this study was to revisit the anatomic information of the male anterior anorectum for intersphincteric resection and abdominoperineal resection with a focus on the spatial muscular morphology. DESIGN: This was a descriptive cadaveric study. SETTINGS: The study was conducted at Ehime and Kyoto universities. PATIENTS: Tissue specimens from 9 male cadavers were included. MAIN OUTCOME MEASURES: Specimens around the anterior anorectum were serially sectioned in the horizontal, sagittal, or frontal plane; large semiserial histologic sections were created at 250-µm intervals. The series were stained with Elastica van Gieson, and some sections from the series were studied by immunohistochemistry to detect smooth and striated muscles. Two series were digitalized and reconstructed 3-dimensionally. RESULTS: Two regions without a clear anatomic border were elucidated: 1) the anterior region of the external anal sphincter, where the external anal sphincter, bulbospongiosus muscle, and superficial transverse perineal muscle were intertwined; and 2) the rectourethralis muscle, where the smooth muscle of the longitudinal muscle continuously extended to the posteroinferior area of the urethra, which became closest to the anorectum at the prostatic apex level. A tight connection between the striated and smooth muscles was identified at the anterior part of the upper external anal sphincter and anterolateral part of the puborectalis muscle level. LIMITATIONS: This study involved a small sample size of elderly cadavers. CONCLUSIONS: This study clarified the precise spatial relationship between smooth and striated muscles. The detailed anatomic findings will contribute more accurate step-by-step anterior dissection in intersphincteric resection and abdominoperineal resection, especially with the transanal approach, which can magnify the muscle fiber direction and contraction of striated muscle by electrostimulation. MORFOLOGÍA TRIDIMENSIONAL PRECISA DEL ANORRECTO ANTERIOR MASCULINO RECONSTRUIDO A TRAVÉS DE SECCIONES MAYORES HISTOLÓGICAS EN SERIE: UN ESTUDIO CADAVÉRICO: El conocimiento anatómico amplio del anorrecto anterior masculino es importante para evitar lesiones de uretra y perforación de recto en la resección interesfinterica o la resección abdominoperineal para cáncer de recto bajo. Sin embargo, su estructura es difícil de entender porque el anorrecto, los músculos y los órganos urogenitales están aliñados en forma complexa tridimensional. OBJETIVO: Revisar de nuevo el conocimiento anatómico del anorrecto anterior masculino relevante a la resección interesfinterica y la resección abdominoperineal con un enfoque en la morfología muscular espacial. DISEÑO:: Estudio descriptivo cadavérico. ENTORNO: Ehime y la Universidad de Kyoto. SUJETOS: Tejido especímenes de nueve cadáveres masculinos. PUNTOS FINALES DE VALORACIÓN:: Las muestras alrededor del anorrecto anterior se seccionaron en serie en planos horizontal, sagital y coronal. Se crearon mayores secciones histológicas en serie a intervalos de 250 µm. Los especímenes fueron teñidos con Elástica van Gieson, y algunas secciones de la serie se estudiaron mediante inmunohistoquímica para detectar músculos lisos y estriados. Dos series fueron digitalizadas y reconstruidas tridimensionalmente. RESULTADOS: Se demostraron dos regiones sin un borde anatómico definido: (i) la región anterior del esfínter anal externo, donde se entrelazaron el esfínter anal externo, el músculo bulbospongoso y el músculo perineal transverso superficial; y (ii) músculo rectouretral, donde el músculo liso del músculo longitudinal se extiende continuamente a la zona posteroinferior de la uretra, que se acerca más al anorrecto a nivel del ápice prostático. La conexión estrecha entre los músculos estriados y lisos se identificó en la parte anterior del esfínter anal externo superior y la parte anterolateral del nivel del músculo puborrectal. LIMITACIÓN:: Este estudio incluyó una muestra pequeña de cadáveres ancianos. CONCLUSIÓN:: Este estudio aclaró la relación espacial precisa entre los músculos lisos y estriados. Los hallazgos anatómicos detallados ayudarán para una disección anterior paso a paso más precisa en la resección interesfintérica y la resección abdominoperineal, especialmente con el abordaje transanal, que puede magnificar la dirección de las fibras musculares y la contracción del músculo estriado utilizando electroestimulación.


Assuntos
Canal Anal/anatomia & histologia , Imageamento Tridimensional/métodos , Músculo Liso/anatomia & histologia , Reto/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , Cadáver , Humanos , Masculino , Reprodutibilidade dos Testes
8.
J Anat ; 235(1): 88-95, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-30977530

RESUMO

In embryology, the infracardiac bursa (ICB) is a well-known derivative separated from the omental bursa. During surgeries around the esophagogastric junction (EGJ), surgeons often encounter a closed space considered to be equivalent to the ICB, but the macroscopic anatomy in adults is hardly known. This study aimed to revisit the ICB using multimodal methods to show its development from the embryonic to adult stage and clarify its persistence and topographic anatomy. Histological sections of 79 embryos from Carnegie stage (CS) 16 to 23 and magnetic resonance (MR) images of 39 fetuses were examined to study the embryological development of the ICB. Horizontal sections around the EGJ obtained from three adult cadavers were examined to determine the topographic anatomy and histology of the ICB. Further, 32 laparoscopic surgical videos before (n = 16) and after (n = 16) the start of this study were reviewed to confirm its remaining rate and topographic anatomy in surgery. The ICB was formed in 1 out of 10 CS17 samples, and in 8 out of 10 CS18 samples. Further, it was observed in all CS19-23 except one CS23 sample and in 25 (64%) out of 39 fetus samples. Three-dimensional reconstructed MR images of fetuses revealed that the ICB was located at the right alongside the esophagus and the cranial side of the diaphragmatic crus. In one adult cadaver, the caudal end of the ICB arose from the level of the esophageal hiatus and the cranial end reached up to the level of the pericardium. The inner surface cells of the space consisted of the mesothelium. In laparoscopic surgery, the ICB was identified in only 11 (69%) out of 16 surgeries before. However, subsequently we were able to identify the ICB reproducibly in 15 (94%) out of 16 surgeries. Thus, the ICB is the structure commonly remaining in almost all adults as a closed space located at the right alongside the esophagus and the cranial side of the diaphragmatic crus. It may be available as a useful landmark in surgery of the EGJ.


Assuntos
Junção Esofagogástrica , Esôfago/anatomia & histologia , Anatomia Regional/métodos , Cadáver , Endoscopia , Junção Esofagogástrica/anatomia & histologia , Junção Esofagogástrica/diagnóstico por imagem , Junção Esofagogástrica/cirurgia , Feminino , Feto/anatomia & histologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino
9.
Nat Commun ; 9(1): 3296, 2018 08 17.
Artigo em Inglês | MEDLINE | ID: mdl-30120246

RESUMO

While menin plays an important role in preventing T-cell dysfunction, such as senescence and exhaustion, the regulatory mechanisms remain unclear. We found that menin prevents the induction of dysfunction in activated CD8 T cells by restricting the cellular metabolism. mTOR complex 1 (mTORC1) signaling, glycolysis, and glutaminolysis are augmented by menin deficiency. Rapamycin treatment prevents CD8 T-cell dysfunction in menin-deficient CD8 T cells. Limited glutamine availability also prevents CD8 T-cell dysfunction induced by menin deficiency, and its inhibitory effect is antagonized by α-ketoglutarate (α-KG), an intermediate metabolite of glutaminolysis. α-KG-dependent histone H3K27 demethylation seems to be involved in the dysfunction in menin-deficient CD8 T cells. We also found that α-KG activates mTORC1-dependent central carbon metabolism. These findings suggest that menin maintains the T-cell functions by limiting mTORC 1 activity and subsequent cellular metabolism.


Assuntos
Linfócitos T CD8-Positivos/imunologia , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Proteínas Proto-Oncogênicas/metabolismo , Ativação Metabólica/efeitos dos fármacos , Animais , Linfócitos T CD8-Positivos/efeitos dos fármacos , Carbono/metabolismo , Proliferação de Células/efeitos dos fármacos , Feminino , Glutamina/metabolismo , Histonas/metabolismo , Ácidos Cetoglutáricos/metabolismo , Ativação Linfocitária/efeitos dos fármacos , Ativação Linfocitária/imunologia , Lisina/metabolismo , Metabolômica , Metilação/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Proteínas Proto-Oncogênicas/deficiência , Sirolimo/farmacologia
10.
Int Cancer Conf J ; 7(3): 77-80, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-31149519

RESUMO

Urethral injury is one of the crucial intraoperative complications during transanal total mesorectal excision (taTME) for male patients with low rectal cancer. Urethral injury can occur during the anterior dissection around the inferior lobe of the prostate and the membranous urethra. A tool to visualize the urethra around this area would be useful to avoid urethral injury. We report a cadaveric demonstration of visualization of the urethra using a lighted stent during transanal intersphincteric resection. The lighted stent (InfraVision Ureteral Kit, Stryker) was placed through the irrigation channel of a clear three-way urinary catheter. After the anterior dissection, the visibility of the lighted stent was investigated under the three laparoscopic light conditions: (1) normal intensity; (2) low intensity; and (3) turned-off. In the proper dissection plane that led to preservation of the urethra, the lighted stent was hardly visible under the normal-intensity condition, but it was clearly visible under the turned-off condition. In the improper dissection plane that led to urethral injury, the lighted stent was clearly visible under both the normal-intensity and the turned-off conditions. Visualization of the urethra using the lighted stent under the turned-off condition of the laparoscopic light can be useful to avoid inadvertent urethral injury during the anterior dissection of male taTME. Clear visibility of the lighted stent under the normal-intensity condition can indicate that the dissection plane is too close to the urethra.

11.
Dis Model Mech ; 10(12): 1421-1432, 2017 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-28982681

RESUMO

Spina bifida aperta (SBA), one of the most common congenital malformations, causes lifelong neurological complications, particularly in terms of motor dysfunction. Fetuses with SBA exhibit voluntary leg movements in utero and during early neonatal life, but these disappear within the first few weeks after birth. However, the pathophysiological sequence underlying such motor dysfunction remains unclear. Additionally, because important insights have yet to be obtained from human cases, an appropriate animal model is essential. Here, we investigated the neuropathological mechanisms of progression of SBA-like motor dysfunctions in a neural tube surgery-induced chicken model of SBA at different pathogenesis points ranging from embryonic to posthatch ages. We found that chicks with SBA-like features lose voluntary leg movements and subsequently exhibit lower-limb paralysis within the first 2 weeks after hatching, coinciding with the synaptic change-induced disruption of spinal motor networks at the site of the SBA lesion in the lumbosacral region. Such synaptic changes reduced the ratio of inhibitory-to-excitatory inputs to motor neurons and were associated with a drastic loss of γ-aminobutyric acid (GABA)ergic inputs and upregulation of the cholinergic activities of motor neurons. Furthermore, most of the neurons in ventral horns, which appeared to be suffering from excitotoxicity during the early postnatal days, underwent apoptosis. However, the triggers of cellular abnormalization and neurodegenerative signaling were evident in the middle- to late-gestational stages, probably attributable to the amniotic fluid-induced in ovo milieu. In conclusion, we found that early neonatal loss of neurons in the ventral horn of exposed spinal cord affords novel insights into the pathophysiology of SBA-like leg dysfunction.


Assuntos
Extremidades/patologia , Extremidades/fisiopatologia , Neurônios Motores/patologia , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Disrafismo Espinal/patologia , Disrafismo Espinal/fisiopatologia , Sinapses/patologia , Animais , Animais Recém-Nascidos , Apoptose , Comportamento Animal , Caspase 3/metabolismo , Embrião de Galinha , Galinhas , Colina/metabolismo , Modelos Animais de Doenças , Interneurônios/patologia , Vértebras Lombares/patologia , Vértebras Lombares/fisiopatologia , Degeneração Neural/patologia , Degeneração Neural/fisiopatologia , Transmissão Sináptica , Ácido gama-Aminobutírico/metabolismo
12.
IBRO Rep ; 3: 17-32, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30135939

RESUMO

Prosaposin (PS) is a secretory neurotrophic factor, as well as a regulator of lysosomal enzymes. We previously reported the up-regulation of PS and the possibility of its axonal transport by GABAergic interneurons after exocitotoxicity induced by kainic acid (KA), a glutamate analog. In the present study, we performed double immunostaining with PS and three calcium binding protein markers: parvalbumin (PV), calbindin, and calretinin, for the subpopulation of GABAergic interneurons, and clarified that the increased PS around the hippocampal pyramidal neurons after KA injection existed mainly in the axons of PV positive interneurons. Electron microscopy revealed PS containing vesicles in the PV positive axon. Double immunostaining with PS and secretogranin or synapsin suggested that PS is secreted with secretogranin from synapses. Based on the results from in situ hybridization with two alternative splicing forms of PS mRNA, the increase of PS in the interneurons was due to the increase of PS + 0 (mRNA without 9-base insertion) as in the choroid plexus, but not PS + 9 (mRNA with 9-base insertion). These results were similar to those from the choroid plexus, which secretes an intact form PS + 0 to the cerebrospinal fluid. Neurons, especially PV positive GABAergic interneurons, produce and secrete the intact form of PS around hippocampal pyramidal neurons to protect them against KA neurotoxicity.

13.
J Alzheimers Dis ; 53(3): 1173-92, 2016 06 30.
Artigo em Inglês | MEDLINE | ID: mdl-27372641

RESUMO

The pathological hallmarks of Alzheimer's disease (AD) include amyloid-ß (Aß) accumulation, neurofibrillary tangle formation, synaptic dysfunction, and neuronal loss. The present study was performed to investigate the protective effects and mechanism of action of a prosaposin-derived 18-mer peptide (PS18: LSELIINNATEELLIKGL) on mice hippocampal progenitor cell proliferation, neurogenesis, and memory tasks after intracerebroventricular injection of Aß1-42 peptide. Seven days after Aß1-42 injection, significant proliferation of hippocampal progenitor cells and memory impairment were evident. Two weeks after Aß1-42 peptide injection, elevated numbers of surviving 5-bromo-2-deoxyuridine cells and newly formed neurons were detected. Treatment with PS18 attenuated these effects evoked by Aß1-42. Our data indicate that treatment with PS18 partially attenuated the increase in hippocampal neurogenesis caused by Aß1-42-induced neuroinflammation and prevented memory deficits associated with increased numbers of activated glial cells. We observed an increase in ADAM10 and decreases in BACE1, PS1/2, and AßPP protein levels, suggesting that PS18 enhances the nonamyloidogenic AßPP cleavage pathway. Importantly, our results further showed that PS18 activated the PI3K/Akt pathway, phosphorylated GSK-3α/ß, and, as a consequence, exerted a neuroprotective effect. In addition, PS18 showed a protective effect against Aß1-42-induced neurotoxicity via suppression of the caspase pathway; upregulation of Bcl-2; downregulation of BAX, attenuating mitochondrial damage; and inhibition of caspase-3. These findings suggest that PS18 may provide a valuable therapeutic strategy for the treatment of progressive neurodegenerative diseases, such as AD.


Assuntos
Peptídeos beta-Amiloides/toxicidade , Hipocampo/efeitos dos fármacos , Transtornos da Memória , Neurogênese/efeitos dos fármacos , Fragmentos de Peptídeos/toxicidade , Peptídeos/farmacologia , Peptídeos/uso terapêutico , Saposinas/química , Acetilcolina/metabolismo , Animais , Proteínas de Ligação ao Cálcio/metabolismo , Colina O-Acetiltransferase/metabolismo , Proteína Glial Fibrilar Ácida/metabolismo , Injeções Intraventriculares , Masculino , Aprendizagem em Labirinto/efeitos dos fármacos , Transtornos da Memória/induzido quimicamente , Transtornos da Memória/tratamento farmacológico , Transtornos da Memória/patologia , Camundongos , Camundongos Endogâmicos C57BL , Proteínas dos Microfilamentos/metabolismo , Fosfopiruvato Hidratase/metabolismo , Distribuição Aleatória , Transdução de Sinais/efeitos dos fármacos , Proteínas tau/metabolismo
14.
PLoS One ; 9(5): e95883, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24871372

RESUMO

Neurogenesis in the hippocampal dentate gyrus occurs constitutively throughout postnatal life. Adult neurogenesis includes a multistep process that ends with the formation of a postmitotic and functionally integrated new neuron. During adult neurogenesis, various markers are expressed, including GFAP, nestin, Pax6, polysialic acid-neural cell adhesion molecule (PSA-NCAM), neuronal nuclei (NeuN), doublecortin, TUC-4, Tuj-1, and calretinin. Prosaposin is the precursor of saposins A-D; it is found in various organs and can be excreted. Strong prosaposin expression has been demonstrated in the developing brain including the hippocampus, and its neurotrophic activity has been proposed. This study investigated changes in prosaposin in the dentate gyrus of young and adult rats using double immunohistochemistry with antibodies to prosaposin, PSA-NCAM, and NeuN. Prosaposin immunoreactivity was intense in the dentate gyrus at postnatal day 3 (P3) and P7, but decreased gradually after P14. In the dentate gyrus at P28, immature PSA-NCAM-positive neurons localized exclusively in the subgranular zone were prosaposin-negative, whereas mature Neu-N-positive neurons were positive for prosaposin. Furthermore, these prosaposin-negative immature neurons were saposin B-positive, suggesting that the neurons take up and degrade prosaposin. In situ hybridization assays showed that prosaposin in the adult dentate gyrus is dominantly the Pro+9 type, a secreted type of prosaposin. These results imply that prosaposin secreted from mature neurons stimulates proliferation and maturation of immature neurons in the dentate gyrus.


Assuntos
Giro Denteado/metabolismo , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Neurogênese/fisiologia , Saposinas/metabolismo , Análise de Variância , Animais , Western Blotting , Giro Denteado/crescimento & desenvolvimento , Proteína Duplacortina , Imuno-Histoquímica , Hibridização In Situ , Microscopia Confocal , Sondas de Oligonucleotídeos/genética , Ratos
15.
Acta Otolaryngol ; 133(5): 462-8, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23216090

RESUMO

CONCLUSION: An 18-mer peptide derived from the neurotrophic region of prosaposin (PS-pep) prevents hearing loss and cochlear damage due to transient cochlear ischaemia by activating an anti-apoptotic pathway. PS-pep is a potent candidate molecule for alleviating ischaemia-induced hearing loss. OBJECTIVE: PS-pep was investigated for its protective effects against ischaemia-induced hearing loss and cochlear damage. METHODS: Ischaemia was induced in both cochleae in Mongolian gerbils by pulling the ligatures around both vertebral arteries in an anterior direction using 5 g weights for 15 min. PS-pep was synthesized artificially and administered subcutaneously four times after the induction of transient cochlear ischaemia. RESULTS: An increase in the auditory brainstem response threshold was alleviated in animals treated with 2.0 mg/kg PS-pep. Histological examinations conducted on day 7 showed that the loss of inner hair cells (IHCs) was more prominent than that of outer hair cells. Higher doses of PS-pep significantly alleviated IHC loss. An increase in the anti-apoptotic factor bcl-2 was also noted in the IHCs treated with PS-pep.


Assuntos
Cóclea/irrigação sanguínea , Perda Auditiva/tratamento farmacológico , Isquemia/complicações , Saposinas/uso terapêutico , Animais , Modelos Animais de Doenças , Potenciais Evocados Auditivos do Tronco Encefálico , Gerbillinae , Perda Auditiva/etiologia , Órgão Espiral/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Saposinas/síntese química
16.
J Neuroimmunol ; 244(1-2): 1-7, 2012 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-22222307

RESUMO

Muscle-specific kinase (MuSK), a receptor tyrosine kinase, is required for the formation and maintenance of neuromuscular junctions (NMJs). Although autoantibodies against MuSK have been demonstrated to cause myasthenia gravis (MG), the underlying pathogenic mechanism remains unclear because a major subclass of these antibodies is functionally monovalent. We investigated the pathogenic role of MuSK antibodies in the onset of MG in vivo and in vitro. Ultrastructural visualization of NMJs in paretic rabbits with MuSK antibodies indicated that postsynaptic membranes were preserved, despite a significant loss of complexity in the convoluted synaptic folds. In addition, an in vitro assay indicated that both divalent and monovalent antibodies from paretic rabbits could interfere with agrin-induced acetylcholine receptor (AChR) clustering in cultured myotubes. Furthermore, in the absence of agrin, divalent antibodies induced MuSK phosphorylation and accelerated downregulation of Dok-7, an essential intracellular MuSK binding protein, while monovalent antibodies inhibited agrin-induced phosphorylation of MuSK, thus demonstrating distinct molecular mechanisms underlying the MuSK dysfunction induced by these two types of antibodies. Taken together, these findings suggest that complement activation is not necessary for the MG onset and that both divalent and monovalent antibodies may cause MG in vivo by inducing MuSK dysfunction.


Assuntos
Autoanticorpos/imunologia , Músculo Esquelético/enzimologia , Miastenia Gravis/imunologia , Receptores Proteína Tirosina Quinases/imunologia , Agrina/farmacologia , Animais , Modelos Animais de Doenças , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/ultraestrutura , Junção Neuromuscular/efeitos dos fármacos , Junção Neuromuscular/imunologia , Coelhos , Receptores Colinérgicos/metabolismo
17.
Neurosci Res ; 71(1): 85-91, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-21658418

RESUMO

Spina bifida aperta (SBA) is an open neural tube defect that occurs during the embryonic period. We created SBA chicks by incising the roof plate of the neural tube in the embryo. The area of the dorsal funiculus was smaller in the SBA chicks than in the normal controls. Additionally, the SBA group had fewer nerve fibres in the dorsal funiculus than the normal controls. The pathway of the ascending sensory nerves was revealed by tracing the degenerated nerve fibres using osmification. We cut the sciatic nerve (L5) of the control and SBA chicks at the central end of the dorsal root ganglion 1 day after hatching and fixed the tissue 3 days later. Degenerated sensory nerve fibres were observed in the ipsilateral dorsal funiculus in the control chicks. In contrast, degenerated sensory nerve fibres were observed in the ipsilateral and contralateral dorsal, ventral and lateral funiculi of the spinal cord in the SBA chicks. Consequently, fewer sensory nerve fibres ascended to the thoracic dorsal funiculus in the SBA chicks than in the normal controls. This is the first report of abnormal changes in the ascending sensory nerve fibres in SBA.


Assuntos
Axônios/patologia , Espinha Bífida Cística/patologia , Medula Espinal/anormalidades , Degeneração Walleriana/patologia , Vias Aferentes/anormalidades , Vias Aferentes/patologia , Vias Aferentes/fisiopatologia , Animais , Embrião de Galinha , Galinhas , Modelos Animais de Doenças , Transtornos Neurológicos da Marcha/etiologia , Transtornos Neurológicos da Marcha/patologia , Transtornos Neurológicos da Marcha/fisiopatologia , Cones de Crescimento/patologia , Membro Posterior/inervação , Membro Posterior/fisiopatologia , Rizotomia/métodos , Células Receptoras Sensoriais/patologia , Espinha Bífida Cística/fisiopatologia , Medula Espinal/patologia , Medula Espinal/fisiopatologia , Raízes Nervosas Espinhais/patologia , Raízes Nervosas Espinhais/fisiopatologia , Raízes Nervosas Espinhais/cirurgia , Degeneração Walleriana/etiologia , Degeneração Walleriana/fisiopatologia
18.
Cell Mol Biol Lett ; 16(2): 279-95, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21394446

RESUMO

We investigated the effects of Rho-associated kinase (ROCK) on migration and cytoskeletal organization in primary human osteoblasts and Saos-2 human osteosarcoma cells. Both cell types were exposed to two different ROCK inhibitors, Y-27632 and HA-1077. In the improved motility assay used in the present study, Y-27632 and HA-1077 significantly increased the migration of both osteoblasts and osteosarcoma cells on plastic in a dose-dependent and reversible manner. Fluorescent images showed that cells of both types cultured with Y-27632 or HA-1077 exhibited a stellate appearance, with poor assembly of stress fibers and focal contacts. Western blotting showed that ROCK inhibitors reduced myosin light chain (MLC) phosphorylation within 5 min without affecting overall myosin light-chain protein levels. Inhibition of ROCK activity is thought to enhance the migration of human osteoblasts through reorganization of the actin cytoskeleton and regulation of myosin activity. ROCK inhibitors may be potentially useful as anabolic agents to enhance the biocompatibility of bone and joint prostheses.


Assuntos
Actomiosina/metabolismo , Osteoblastos/metabolismo , Inibidores de Proteínas Quinases/farmacologia , Quinases Associadas a rho/antagonistas & inibidores , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/análogos & derivados , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina/farmacologia , Amidas/farmacologia , Movimento Celular , Células Cultivadas , Adesões Focais , Humanos , Cadeias Leves de Miosina/metabolismo , Fosforilação , Piridinas/farmacologia , Fibras de Estresse , Quinases Associadas a rho/metabolismo
19.
J Vet Med Sci ; 73(4): 447-52, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21127393

RESUMO

Spina bifida aperta (SBA) is a congenital malformation of the spinal cord with complications such as spinal ataxia and bowel and bladder dysfunction. We have developed a chick model with surgery-induced SBA that shows spinal ataxia after hatching. In the present study, motor neurons in the early stages in chicks with and without SBA were observed by immunohistochemical staining with a monoclonal antibody against Islet-1, a motor neuron marker. Delay in migration and maturation of motor neurons was observed in SBA. Although the final numbers of Islet-1-positive neurons in these two groups were not different, a defect in the production and elimination of excess motor neurons in the early developmental stages in the SBA group may be involved in the pathological mechanism of the motor complications of this disease.


Assuntos
Galinhas , Proteínas de Homeodomínio/metabolismo , Neurônios/fisiologia , Doenças das Aves Domésticas/metabolismo , Espinha Bífida Cística/veterinária , Medula Espinal/citologia , Animais , Regulação da Expressão Gênica no Desenvolvimento/fisiologia , Proteínas de Homeodomínio/genética , Proteínas com Homeodomínio LIM , Doenças das Aves Domésticas/fisiopatologia , Espinha Bífida Cística/metabolismo , Espinha Bífida Cística/fisiopatologia , Fatores de Transcrição
20.
Ophthalmic Surg Lasers Imaging ; 39(2): 167-70, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-18435347

RESUMO

The influence of the height of the superomedial orbital rim on the ease of nasolacrimal intubation has not been investigated. The authors measured the inclination of the height of the superomedial orbital rim and the nasolacrimal drainage system in 46 sides of Japanese cadavers. The inclinations to the coronal plane of the lacrimal sac and the nasolacrimal duct were measured. A straight probe was inserted into the lacrimal sac and allowed to rest on the superomedial orbital rim. The angle made by this probe and the coronal plane, defined as the inclination of the height of the superomedial orbital rim, was measured. The lacrimal sac was inclined 27.2 degrees +/- 7.6 degrees, the nasolacrimal duct was inclined 22.5 degrees +/- 9.7 degrees, and the height of the superomedial orbital rim was inclined 26.1 degrees +/- 9.1 degrees. For the height of the superomedial orbital rim-nasolacrimal duct angle, there were 33 sides with the anterior type and 13 sides with the posterior type. These results indicate that the height of the superomedial orbital rim may affect the ease of nasolacrimal intubation.


Assuntos
Ducto Nasolacrimal/anatomia & histologia , Órbita/anatomia & histologia , Idoso , Idoso de 80 Anos ou mais , Dacriocistorinostomia , Feminino , Humanos , Intubação , Masculino
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA