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1.
J Vasc Surg Venous Lymphat Disord ; : 101903, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38754777

RESUMO

OBJECTIVE: Non-vitamin K antagonist oral anticoagulants have shown similar efficacy and lower bleeding rates than vitamin K antagonists for venous thromboembolism. However, this has not been proven in mesenteric vein thrombosis. This study aimed to compare the clinical outcomes of vitamin K antagonists and non-vitamin K antagonist oral anticoagulants. METHODS: Between January 2014 and July 2022, mesenteric vein thrombosis was diagnosed on computed tomography in 225 patients in a tertiary hospital. Among them, a total of 44 patients who underwent long-term anticoagulation therapy over 3 months were enrolled in this study. Patients were divided into two groups based on the anticoagulant used: vitamin K antagonists (Group 1, n = 21) and non-vitamin K antagonist oral anticoagulants (Group 2, n = 23). The efficacy outcomes were symptom recurrence and thrombus resolution on follow-up computed tomography, and the safety outcome was bleeding complications. RESULTS: The median age of the patients was 56 years (range, 46-68 years), and 52% were men. The most common risk factors were unprovoked intra-abdominal infections (30%). The median duration of anticoagulation therapy was 13 months (20 months in Group 1 vs 6 months in Group 2; P = .076). Of the 44 patients, 17 (39%) received the standard treatment. The median follow-up period was longer in Group 1 than in Group 2 (57 vs 28 months; P = .048). No recurrence of mesenteric vein thrombosis-related symptoms were observed in either group. The median duration of follow-up computed tomography was 31 months (42 months in Group 1 vs 18 months in Group 2; P = .064). Computed tomography revealed complete thrombus resolution, partial resolution, and no changes in 71%, 19%, and 10%, respectively (P = .075). Regarding bleeding complications, varix bleeding and melena developed in two patients in Group 2, and anticoagulation treatment thereafter ceased. CONCLUSIONS: Despite the short follow-up duration in the non-vitamin K antagonist oral anticoagulants group, there was no clinically significant difference in the thrombus resolution rate or bleeding complications when compared with the vitamin K antagonists group. Although research on the long-term effects of non-vitamin K antagonist oral anticoagulants in patients is limited, non-vitamin K antagonist oral anticoagulants can be considered an alternative to conventional treatments.

2.
Theranostics ; 14(1): 56-74, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38164158

RESUMO

Rationale: Promotion of mitophagy is considered a promising strategy for the treatment of neurodegenerative diseases including Alzheimer's disease (AD). The development of mitophagy-specific inducers with low toxicity and defined molecular mechanisms is essential for the clinical application of mitophagy-based therapy. The aim of this study was to investigate the potential of a novel small-molecule mitophagy inducer, ALT001, as a treatment for AD. Methods: ALT001 was developed through chemical optimization of an isoquinolium scaffold, which was identified from a chemical library screening using a mitophagy reporter system. In vitro and in vivo experiments were conducted to evaluate the potential of ALT001 as a mitophagy-targeting therapeutic agent and to investigate the molecular mechanisms underlying ALT001-induced mitophagy. The therapeutic effect of ALT001 was assessed in SH-SY5Y cells expressing mutant APP and mouse models of AD (5×FAD and PS2APP) by analyzing mitochondrial dysfunction and cognitive defects. Results: ALT001 specifically induces mitophagy both in vitro and in vivo but is nontoxic to mitochondria. Interestingly, we found that ALT001 induces mitophagy through the ULK1-Rab9-dependent alternative mitophagy pathway independent of canonical mitophagy pathway regulators such as ATG7 and PINK1. Importantly, ALT001 reverses mitochondrial dysfunction in SH-SY5Y cells expressing mutant APP in a mitophagy-dependent manner. ALT001 induces alternative mitophagy in mice and restores the decreased mitophagy level in a 5×FAD AD model mouse. In addition, ALT001 reverses mitochondrial dysfunction and cognitive defects in the PS2APP and 5×FAD AD mouse models. AAV-mediated silencing of Rab9 in the hippocampus further confirmed that ALT001 exerts its therapeutic effect through alternative mitophagy. Conclusion: Our results highlight the therapeutic potential of ALT001 for AD via alleviation of mitochondrial dysfunction and indicate the usefulness of the ULK1-Rab9 alternative mitophagy pathway as a therapeutic target.


Assuntos
Doença de Alzheimer , Doenças Mitocondriais , Neuroblastoma , Humanos , Camundongos , Animais , Doença de Alzheimer/metabolismo , Mitofagia , Modelos Animais de Doenças , Isoquinolinas/farmacologia , Cognição
3.
FASEB J ; 35(1): e21225, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33337568

RESUMO

Studies of neuroglial interaction largely depend on cell-specific gene knockout (KO) experiments using Cre recombinase. However, genes known as glial-specific genes have recently been reported to be expressed in neuroglial stem cells, leading to the possibility that a glia-specific Cre driver results in unwanted gene deletion in neurons, which may affect sound interpretation. 2',3'-Cyclic nucleotide 3'-phosphodiesterase (CNP) is generally considered to be an oligodendrocyte (OL) marker. Accordingly, Cnp promoter-controlled Cre recombinase has been used to create OL-specific gene targeting mice. However, in this study, using Rosa26-tdTomato-reporter/Cnp-Cre mice, we found that many forebrain neurons and cerebellar Purkinje neurons belong to the lineages of Cnp-expressing neuroglial stem cells. To answer whether gene targeting by Cnp-Cre can induce neuron-autonomous defects, we conditionally deleted an essential autophagy gene, Atg7, in Cnp-Cre mice. The Cnp-Cre-mediated Atg7 KO mice showed extensive p62 inclusion in neurons, including cerebellar Purkinje neurons with extensive neurodegeneration. Furthermore, neuronal areas showing p62 inclusion in Cnp-Cre-mediated Atg7 KO mice overlapped with the neuronal lineage of Cnp-expressing neuroglial stem cells. Moreover, Cnp-Cre-mediated Atg7-KO mice did not develop critical defects in myelination. Our results demonstrate that a large population of central neurons are derived from Cnp-expressing neuroglial stem cells; thus, conditional gene targeting using the Cnp promoter, which is known to be OL-specific, can induce neuron-autonomous phenotypes.


Assuntos
2',3'-Nucleotídeo Cíclico 3'-Fosfodiesterase/deficiência , Doenças Neurodegenerativas/enzimologia , Neuroglia/enzimologia , Células de Purkinje/enzimologia , Células-Tronco/enzimologia , 2',3'-Nucleotídeo Cíclico 3'-Fosfodiesterase/metabolismo , Animais , Proteína 7 Relacionada à Autofagia/genética , Integrases/genética , Integrases/metabolismo , Camundongos , Camundongos Knockout , Doenças Neurodegenerativas/genética , Doenças Neurodegenerativas/patologia , Neuroglia/patologia , Células de Purkinje/patologia , Células-Tronco/patologia
4.
World J Clin Cases ; 8(17): 3821-3827, 2020 Sep 06.
Artigo em Inglês | MEDLINE | ID: mdl-32953859

RESUMO

BACKGROUND: Gastrointestinal subepithelial tumors (GSTs), incidentally detected during upper gastrointestinal (GI) endoscopy, may be lesions derived from the GI wall or may be caused by compression from external organs. In general, traumatic neuroma is a benign nerve tumor that results from postoperative nerve injury, occurring in the bile duct as one of the complications after cholecystectomy. This is the first case report demonstrating that neuroma of the cystic duct can be incorrectly perceived as a duodenal subepithelial tumor by compressing the duodenal wall. CASE SUMMARY: We report the case of a 72-year-old man with traumatic neuroma of the cystic duct after cholecystectomy. This tumor was mistaken for a duodenal subepithelial tumor on preoperative upper GI endoscopy and endoscopic ultrasonography due to external compression of the GI wall. The patient had no symptoms, and his laboratory test results were normal. However, in a series of follow-up endoscopies, the tumor was found to have grown in size, so it was surgically resected. The lesion was completely removed by laparoscopic endoscopic cooperative surgery. The patient was discharged on postoperative day 7 without complications. CONCLUSION: Traumatic neuroma of the cystic duct can be mistaken for GSTs in GI endoscopy.

5.
Ann Clin Transl Neurol ; 6(7): 1292-1301, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31353867

RESUMO

OBJECTIVE: Myelinated Schwann cells (SCs) in adult peripheral nerves dedifferentiate into immature cells in demyelinating neuropathies and Wallerian degeneration. This plastic SC change is actively involved in the myelin destruction and clearance as demyelinating SCs (DSCs). In inherited demyelinating neuropathy, pathologically differentiated and dysmyelinated SCs constitute the main nerve pathology. METHODS: We investigated whether this SC plastic status in human neuropathic nerves could be determined by patient sera to develop disease-relevant serum biomarkers. Based on proteomics analysis of the secreted exosomes from immature SCs, we traced p75 neurotrophin receptor (p75) and neural cell adhesion molecule 1 (NCAM) in the sera of patients with peripheral neuropathy. RESULTS: Enzyme-linked immunosorbent assay (ELISA) revealed that p75 and NCAM were subtype-specifically expressed in the sera of patients with peripheral neuropathy. In conjunction with these ELISA data, pathological analyses of animal models and human specimens suggested that the presence of DSCs in inflammatory neuropathy and of supernumerary nonmyelinating or dysmyelinating SCs in inherited neuropathy could potentially be distinguished by comparing the expression profiles of p75 and NCAM. INTERPRETATION: This study indicates that the identification of disease-specific pathological SC stages might be a valuable tool for differential diagnosis of peripheral neuropathies.


Assuntos
Antígeno CD56/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Doenças do Sistema Nervoso Periférico/metabolismo , Receptores de Fator de Crescimento Neural/metabolismo , Células de Schwann/metabolismo , Animais , Antígeno CD56/sangue , Doenças Desmielinizantes/metabolismo , Feminino , Humanos , Masculino , Camundongos Endogâmicos C57BL , Bainha de Mielina/metabolismo , Bainha de Mielina/patologia , Proteínas do Tecido Nervoso/sangue , Doenças do Sistema Nervoso Periférico/sangue , Receptores de Fator de Crescimento Neural/sangue , Células de Schwann/patologia
6.
Transplant Proc ; 51(6): 1853-1860, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31256871

RESUMO

OBJECTIVE: The development of sarcopenia leads to adverse postoperative outcomes. However, no study has investigated perioperative loss in core muscle and the correlation between core muscle and residual liver volume in living donors for liver transplant. PATIENTS AND METHODS: A total of 457 adult healthy donors who underwent a right lobe hepatectomy without the middle hepatic vein for elective liver transplant were retrospectively analyzed. Abdominal computed tomography was performed within 1 month before surgery and the first week and 3 months after the surgery. The average psoas muscle area between lumbar vertebrae 3 and 4 was measured and normalized by height squared (psoas muscle index [PMI] = psoas muscle area/height2). The initial whole liver volume and remnant left lobe volume were measured on computed tomography images. RESULTS: The study cohort included 279 men (61.1%) and 178 women (38.9%). The median preoperative PMIs were 420.9 mm2/m2 (interquartile range, 360.6-487.0 mm2/m2) in men and 280.9 mm2/m2 (interquartile range, 243.5-318.7 mm2/m2) in women. The PMIs in men and women significantly decreased during the first week after surgery, and gradually recovered to preoperative levels during the first 3 months after surgery. Based on the ratio between the remnant left lobe and initial whole liver volume (≥30%), the increase in remnant left lobe volume was not correlated with the decrease in PMI on postoperative day 7. A postoperative U-shaped recovery in the core muscles was present in both male and female donors, independent of the remnant liver ratio. CONCLUSIONS: Despite the requirements of partial liver regeneration and surgical wound repair, healthy donors did not suffer from sustained core muscle loss after surgery.


Assuntos
Hepatectomia/efeitos adversos , Doadores Vivos , Complicações Pós-Operatórias/fisiopatologia , Músculos Psoas/fisiopatologia , Coleta de Tecidos e Órgãos/efeitos adversos , Adulto , Feminino , Hepatectomia/métodos , Veias Hepáticas , Humanos , Fígado/patologia , Fígado/cirurgia , Regeneração Hepática , Transplante de Fígado , Masculino , Pessoa de Meia-Idade , Tamanho do Órgão , Complicações Pós-Operatórias/etiologia , Período Pós-Operatório , Músculos Psoas/cirurgia , Recuperação de Função Fisiológica , Estudos Retrospectivos , Sarcopenia/etiologia , Sarcopenia/fisiopatologia , Tomografia Computadorizada por Raios X
7.
Front Pharmacol ; 10: 1653, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-32063857

RESUMO

Numerous clinical trials of drug candidates for Alzheimer's disease (AD) have failed, and computational drug repositioning approaches using omics data have been proposed as effective alternative approaches to the discovery of drug candidates. However, little multi-omics data is available for AD, due to limited availability of brain tissues. Even if omics data exist, systematic drug repurposing study for AD has suffered from lack of big data, insufficient clinical information, and difficulty in data integration on account of sample heterogeneity derived from poor diagnosis or shortage of qualified post-mortem tissue. In this study, we developed a proteotranscriptomic-based computational drug repositioning method named Drug Repositioning Perturbation Score/Class (DRPS/C) based on inverse associations between disease- and drug-induced gene and protein perturbation patterns, incorporating pharmacogenomic knowledge. We constructed a Drug-induced Gene Perturbation Signature Database (DGPSD) comprised of 61,019 gene signatures perturbed by 1,520 drugs from the Connectivity Map (CMap) and the L1000 CMap. Drugs were classified into three DRPCs (High, Intermediate, and Low) according to DRPSs that were calculated using drug- and disease-induced gene perturbation signatures from DGPSD and The Cancer Genome Atlas (TCGA), respectively. The DRPS/C method was evaluated using the area under the ROC curve, with a prescribed drug list from TCGA as the gold standard. Glioblastoma had the highest AUC. To predict anti-AD drugs, DRPS were calculated using DGPSD and AD-induced gene/protein perturbation signatures generated from RNA-seq, microarray and proteomic datasets in the Synapse database, and the drugs were classified into DRPCs. We predicted 31 potential anti-AD drug candidates commonly belonged to high DRPCs of transcriptomic and proteomic signatures. Of these, four drugs classified into the nervous system group of Anatomical Therapeutic Chemical (ATC) system are voltage-gated sodium channel blockers (bupivacaine, topiramate) and monamine oxidase inhibitors (selegiline, iproniazid), and their mechanism of action was inferred from a potential anti-AD drug perspective. Our approach suggests a shortcut to discover new efficacy of drugs for AD.

8.
eNeuro ; 5(4)2018.
Artigo em Inglês | MEDLINE | ID: mdl-30079376

RESUMO

ß-Site amyloid precursor protein cleaving enzyme 1 (BACE1) is required for the production of ß-amyloid (Aß), one of the major pathogenic molecules of Alzheimer's disease (AD), and is therefore being actively pursued as a drug target for AD. Adult hippocampal neurogenesis (AHN) is a lifelong process that is known to be important for learning and memory and may have the potential to regenerate damaged neural tissue. In this study, we examined whether BACE1 regulates AHN, which holds important implications for its suitability as a drug target in AD. Cohorts of 2-month-old wild-type (BACE1+/+), heterozygous, and homozygous BACE1 knockout mice (BACE1+/- and BACE1-/-, respectively) were injected with 5-bromo-2'-deoxyuridine (BrdU) and sacrificed 1 day later to examine the impact of loss of BACE1 on neural precursor cell (NPC) proliferation in the adult brain. Parallel cohorts of mice were sacrificed 4 weeks after BrdU injection to determine the effects of BACE1 on survival and differentiation of newborn NPCs. We found that NPC proliferation was increased in BACE1-/- mice compared to BACE1+/+ mice, while no difference was observed in NPC survival across genotypes. Differentiation of NPCs to neuronal lineage was impaired in BACE1-/- mice. However, no differences were observed in astrogenesis, the proportion of immature neurons, or the production of oligodendrocytes across genotypes. Importantly, corresponding with a decrease in neuronal differentiation in the absence of a complementary increase in an alternate cell fate, BACE1-/- mice were found to have a pool of undifferentiated NPCs in the hippocampus compared to BACE1+/+ and BACE1+/- mice.


Assuntos
Secretases da Proteína Precursora do Amiloide/fisiologia , Ácido Aspártico Endopeptidases/fisiologia , Diferenciação Celular/fisiologia , Proliferação de Células/fisiologia , Hipocampo/fisiologia , Neurogênese/fisiologia , Neurônios/fisiologia , Fatores Etários , Animais , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout
9.
Lab Chip ; 18(17): 2604-2613, 2018 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-30043033

RESUMO

The microfluidic 3D cell culture system has been an attractive model because it mimics the tissue and disease model, thereby expanding our ability to control the local cellular microenvironment. However, these systems still have limited value as quantitative assay tools due to the difficulties associated with the manipulation and maintenance of microfluidic cells, and their lack of compatibility with the high-throughput screening (HTS) analysis system. In this study, we suggest a microchannel-free, 3D cell culture system that has a hydrogel-incorporating unit integrated with a multi-well plate (24- to 96-well plate), which can provide better reproducibility in biological experiments. This plate was devised considering the design constraints imposed by various cell biology applications as well as by high-throughput analysis where the physical dimensions of the micro-features in the hydrogel-incorporating units were altered. We also demonstrated that the developed plate is potentially applicable to a variety of quantitative biochemical assays for qRT-PCR, Western blotting, and microplate-reader-based assays, such as ELISA, viability assay, and high content-screening (HCS) as well as the co-culture for biological studies. Human neural progenitor cells (hNPCs) that produce pathogenic Aß species for modeling Alzheimer's disease (AD) were three-dimensionally cultured, and the efficacy of the inhibitors of Aß production was assessed by ELISA in order to demonstrate the performance of this plate.


Assuntos
Técnicas de Cultura de Células/instrumentação , Hidrogéis/química , Dispositivos Lab-On-A-Chip , Diferenciação Celular , Ensaios de Triagem em Larga Escala , Humanos
10.
Neuropathology ; 37(6): 560-568, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28748542

RESUMO

A 16-year-old boy presented with marked weight loss, weakness of the left extremities and dizziness of 2 months duration and vomiting for 2 days. Brain MRI showed an approximately 6.5 × 5.3 cm-sized huge heterogeneous enhancing mass located in the corpus callosum, extending into the lateral ventricle. Open biopsy showed that the lesion consisted of lymphoplasmacytes and plump histiocytes with rhabdoid morphology, which were stained with S-100 protein, CD68 (KP1) and negative for CD1a. Histiocytic tumor was initially diagnosed. Chemotherapy using methotrexate, 6-mercaptopurine, vinblastine, interferon-alpha and dexamethasone was performed. After 5 months, partial removal was done. Microscopically, plump and bizarre tumor cells as well as rhabdoid features were found. Occasional spindle cells and necrosis were also found. These cells were positive for CD163, CD68, lysozyme, CD4, INI-1 and BRG1. BRAF V600E mutation was detected. The lesion was finally diagnosed as histiocytic sarcoma. Radiotherapy (6000 cGy in 30 fractions) was done. Both cerebral and extracerebral histiocytic sarcomas have long been diagnosed by unclarified criteria; its rarity as well as previously unclarified criteria can easily lead to a misinterpretation. Histiocytic sarcoma of the CNS is exceptionally rare in children, associated with an exceptionally poor prognosis. To date, only seven cases of pediatric cerebral histiocytic sarcomas have been reported. The present case is the first pediatric case showing BRAF V600E-mutated intracerebral histiocytic sarcoma.


Assuntos
Neoplasias Encefálicas/patologia , Sarcoma Histiocítico/patologia , Adolescente , Humanos , Masculino
11.
Artigo em Inglês | MEDLINE | ID: mdl-28642733

RESUMO

Ectopic adrenocorticotropic hormone (ACTH) syndrome is a challenging diagnosis only responsible for approximately 10% of Cushing syndrome cases. It has been associated with a variety of benign and malignant tumors including a carcinoid tumor accompanied by aspergilloma in our case that was significantly difficult to be detected. We report a patient over 70 years old with uncontrolled hypertension and hypokalemia presenting with generalized edema. Laboratory results revealed ACTH-dependent Cushing syndrome, but imaging studies did not show any discrete lesions secreting ACTH. The petrosal to peripheral ACTH gradient resulted in no evidence of pituitary adenoma. As the only lesion suspicious for ectopic ACTH secretion was a right lower round cystic lesion that did not appear to be a carcinoid tumor on computed tomography scan of the chest, the patient underwent video-assisted thoracic surgical resection to provide a definitive diagnosis. The final diagnosis was a small ectopic ACTH-secreting carcinoid tumor with unusual superimposed aspergilloma in the periphery of the lung. Postoperatively, the abnormal endocrine levels were normalized, and all of the clinical symptoms and signs were ameliorated. This is an informative case of ectopic ACTH syndrome (EAS) that was the cause of hypokalemia, hypertension, metabolic alkalosis, and hypercortisolism despite its poorly specific cushingoid morphology and uncommon imaging findings. Therefore, we recommend that clinicians investigate any possible lesion as a potential source of EAS.

12.
Mol Neurodegener ; 11(1): 75, 2016 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-27938410

RESUMO

Alzheimer's disease (AD) transgenic mice have been used as a standard AD model for basic mechanistic studies and drug discovery. These mouse models showed symbolic AD pathologies including ß-amyloid (Aß) plaques, gliosis and memory deficits but failed to fully recapitulate AD pathogenic cascades including robust phospho tau (p-tau) accumulation, clear neurofibrillary tangles (NFTs) and neurodegeneration, solely driven by familial AD (FAD) mutation(s). Recent advances in human stem cell and three-dimensional (3D) culture technologies made it possible to generate novel 3D neural cell culture models that recapitulate AD pathologies including robust Aß deposition and Aß-driven NFT-like tau pathology. These new 3D human cell culture models of AD hold a promise for a novel platform that can be used for mechanism studies in human brain-like environment and high-throughput drug screening (HTS). In this review, we will summarize the current progress in recapitulating AD pathogenic cascades in human neural cell culture models using AD patient-derived induced pluripotent stem cells (iPSCs) or genetically modified human stem cell lines. We will also explain how new 3D culture technologies were applied to accelerate Aß and p-tau pathologies in human neural cell cultures, as compared the standard two-dimensional (2D) culture conditions. Finally, we will discuss a potential impact of the human 3D human neural cell culture models on the AD drug-development process. These revolutionary 3D culture models of AD will contribute to accelerate the discovery of novel AD drugs.


Assuntos
Doença de Alzheimer , Técnicas de Cultura de Células , Células-Tronco Neurais/citologia , Humanos
13.
Chem Commun (Camb) ; 52(79): 11764-11767, 2016 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-27711355

RESUMO

Herein, we present a simple readout of the binding between a chemical drug and its target proteins in the cytoplasm by using a two-step bioorthogonal labeling method combined with spatially-localized expression of proteins. Dasatinib was modified with trans-cyclooctene (TCO), and its cytoplasmic target kinases were expressed in intracellular compartments, such as endosomes and F-actins. After bioorthogonal labeling, the colocalization between Dasatinib and its target proteins was observed in intracellular compartments.


Assuntos
Actinas/metabolismo , Dasatinibe/metabolismo , Microscopia de Fluorescência , Proteínas Quinases/metabolismo , Actinas/química , Proteína Tirosina Quinase CSK , Ciclo-Octanos/química , Citoplasma/metabolismo , Dasatinibe/química , Endossomos/metabolismo , Células HeLa , Humanos , Ligação Proteica , Proteínas Quinases/química , Quinases da Família src/química , Quinases da Família src/metabolismo
14.
Bioessays ; 37(10): 1139-48, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26252541

RESUMO

Alzheimer's disease (AD) is the most common cause of dementia, and there is currently no cure. The "ß-amyloid cascade hypothesis" of AD is the basis of current understanding of AD pathogenesis and drug discovery. However, no AD models have fully validated this hypothesis. We recently developed a human stem cell culture model of AD by cultivating genetically modified human neural stem cells in a three-dimensional (3D) cell culture system. These cells were able to recapitulate key events of AD pathology including ß-amyloid plaques and neurofibrillary tangles. In this review, we will discuss the progress and current limitations of AD mouse models and human stem cell models as well as explore the breakthroughs of 3D cell culture systems. We will also share our perspective on the potential of dish models of neurodegenerative diseases for studying pathogenic cascades and therapeutic drug discovery.


Assuntos
Doença de Alzheimer/patologia , Técnicas de Cultura de Células/métodos , Células-Tronco Neurais/patologia , Precursor de Proteína beta-Amiloide/genética , Animais , Modelos Animais de Doenças , Humanos , Camundongos , Células-Tronco Neurais/citologia
15.
Nat Protoc ; 10(7): 985-1006, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26068894

RESUMO

Stem cell technologies have facilitated the development of human cellular disease models that can be used to study pathogenesis and test therapeutic candidates. These models hold promise for complex neurological diseases such as Alzheimer's disease (AD), because existing animal models have been unable to fully recapitulate all aspects of pathology. We recently reported the characterization of a novel 3D culture system that exhibits key events in AD pathogenesis, including extracellular aggregation of amyloid-ß (Aß) and accumulation of hyperphosphorylated tau. Here we provide instructions for the generation and analysis of 3D human neural cell cultures, including the production of genetically modified human neural progenitor cells (hNPCs) with familial AD mutations, the differentiation of the hNPCs in a 3D matrix and the analysis of AD pathogenesis. The 3D culture generation takes 1-2 d. The aggregation of Aß is observed after 6 weeks of differentiation, followed by robust tau pathology after 10-14 weeks.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Modelos Neurológicos , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Técnicas de Cultura de Células/métodos , Diferenciação Celular , Linhagem Celular , Humanos , Mutação , Agregação Patológica de Proteínas/metabolismo , Proteínas tau/metabolismo
16.
US Neurol ; 11(2): 102-105, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27019672

RESUMO

The "amyloid ß hypothesis" of Alzheimer's disease (AD) has been the reigning hypothesis explaining pathogenic mechanisms of AD over the last two decades. However, this hypothesis has not been fully validated in animal models, and several major unresolved issues remain. We recently developed a human neural cell culture model of AD based on a three-dimensional (3D) cell culture system. This unique, cellular model recapitulates key events of the AD pathogenic cascade, including ß-amyloid plaques and neurofibrillary tangles. Our 3D human neural cell culture model system provides a premise for a new generation of cellular AD models that can serve as a novel platform for studying pathogenic mechanisms and for high-throughput drug screening in a human brain-like environment.

17.
J Proteome Res ; 14(1): 214-23, 2015 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-25384129

RESUMO

Microglial activation in the central nervous system is a key event in the neuroinflammation that accompanies neurodegenerative diseases such as Alzheimer's disease (AD). Among cytokines involved in microglial activation, amyloid ß (Aß) peptide is known to be a key molecule in the induction of diverse inflammatory products, which may lead to chronic inflammation in AD. However, proteomic studies of microglia in AD are limited due to lack of proper cell or animal model systems. In this study, we performed a proteomic analysis of Aß-stimulated human microglial cells using SILAC (stable isotope labeling with amino acids in cell culture) combined with LC-MS/MS. Results showed that 60 proteins increased or decreased their abundance by 1.5 fold or greater. Among these, ER-resident proteins such as SERPINH1, PDIA6, PDIA3, and PPIB were revealed to be key molecular biomarkers of human microglial activation by validation of the proteomic results by immunostaining, PCR, ELISA, and Western blot. Taken together, our data suggest that ER proteins play an essential role in human microglial activation by Aß and may be important molecular therapeutic targets for treatment of AD.


Assuntos
Peptídeos beta-Amiloides/fisiologia , Retículo Endoplasmático/metabolismo , Proteínas de Membrana/metabolismo , Microglia/fisiologia , Proteoma/metabolismo , Doença de Alzheimer/metabolismo , Sequência de Aminoácidos , Animais , Biomarcadores/metabolismo , Linhagem Celular , Expressão Gênica , Ontologia Genética , Humanos , Camundongos , Dados de Sequência Molecular , Mapeamento de Interação de Proteínas , Proteoma/genética , Proteômica , Espectrometria de Massas em Tandem
18.
Nature ; 515(7526): 274-8, 2014 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-25307057

RESUMO

Alzheimer's disease is the most common form of dementia, characterized by two pathological hallmarks: amyloid-ß plaques and neurofibrillary tangles. The amyloid hypothesis of Alzheimer's disease posits that the excessive accumulation of amyloid-ß peptide leads to neurofibrillary tangles composed of aggregated hyperphosphorylated tau. However, to date, no single disease model has serially linked these two pathological events using human neuronal cells. Mouse models with familial Alzheimer's disease (FAD) mutations exhibit amyloid-ß-induced synaptic and memory deficits but they do not fully recapitulate other key pathological events of Alzheimer's disease, including distinct neurofibrillary tangle pathology. Human neurons derived from Alzheimer's disease patients have shown elevated levels of toxic amyloid-ß species and phosphorylated tau but did not demonstrate amyloid-ß plaques or neurofibrillary tangles. Here we report that FAD mutations in ß-amyloid precursor protein and presenilin 1 are able to induce robust extracellular deposition of amyloid-ß, including amyloid-ß plaques, in a human neural stem-cell-derived three-dimensional (3D) culture system. More importantly, the 3D-differentiated neuronal cells expressing FAD mutations exhibited high levels of detergent-resistant, silver-positive aggregates of phosphorylated tau in the soma and neurites, as well as filamentous tau, as detected by immunoelectron microscopy. Inhibition of amyloid-ß generation with ß- or γ-secretase inhibitors not only decreased amyloid-ß pathology, but also attenuated tauopathy. We also found that glycogen synthase kinase 3 (GSK3) regulated amyloid-ß-mediated tau phosphorylation. We have successfully recapitulated amyloid-ß and tau pathology in a single 3D human neural cell culture system. Our unique strategy for recapitulating Alzheimer's disease pathology in a 3D neural cell culture model should also serve to facilitate the development of more precise human neural cell models of other neurodegenerative disorders.


Assuntos
Doença de Alzheimer/metabolismo , Doença de Alzheimer/patologia , Técnicas de Cultura de Células/métodos , Modelos Biológicos , Células-Tronco Neurais/metabolismo , Doença de Alzheimer/genética , Peptídeos beta-Amiloides/química , Peptídeos beta-Amiloides/genética , Peptídeos beta-Amiloides/metabolismo , Diferenciação Celular , Avaliação Pré-Clínica de Medicamentos/métodos , Espaço Extracelular/metabolismo , Quinase 3 da Glicogênio Sintase/metabolismo , Humanos , Proteínas Associadas aos Microtúbulos/metabolismo , Células-Tronco Neurais/patologia , Neuritos/metabolismo , Fosforilação , Presenilina-1/metabolismo , Agregação Patológica de Proteínas , Reprodutibilidade dos Testes , Proteínas tau/química , Proteínas tau/metabolismo
19.
Hippocampus ; 24(6): 628-42, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24449190

RESUMO

Although there are many types of epilepsy, temporal lobe epilepsy (TLE) is probably in humans the most common and most often studied. TLE represents 40% of the total epilepsy form of the disease and is difficult to treat. Despite a wealth of descriptive data obtained from the disease history of patients, the EEG recording, imaging techniques, and histological studies, the epileptogenic process remains poorly understood. However, it is unlikely that a single factor or a single mechanism can cause many changes associated with this neuropathological phenomenon. MALDI mass spectrometry imaging (MSI) coupled to protein identification, because of its ability to study a wide range of molecules, appears to be suitable for the preparation of molecular profiles in TLE. Seven neuropeptides have been have been identified in Dental gyrus regions of the hippocampus in relation with TLE pathology. Shot-gun studies taking into account gender influence have been performed. Tissue microextraction from control (10) toward 10 TLE patients have been analyzed after trypsin digestion followed by separation on nanoLC coupled to LTQ orbitrap. From the shot-gun analyses, results confirmed the presence of specific neuropeptides precursors and receptors in TLE patients as well as proteins involved in axons regeneration including neurotrophins, ECM proteins, cell surface proteins, membrane proteins, G-proteins, cytoskeleton proteins and tumor suppressors. Among the tumor suppressors identified, the Leucine-rich glioma inactivated 1 (LGI1) protein was found. LGI1 gene recently been demonstrated being implicated in heritability of TLE. We have also demonstrate the presence a complete profile of tumor suppressors in TLE patients, 7 have been identified. Refining this analysis taken into account the gender influence in both control and in TLE reflected the presence of specific proteins between male and female and thus mechanisms in pathology development could be completely different.


Assuntos
Epilepsia do Lobo Temporal/metabolismo , Hipocampo/metabolismo , Proteômica/métodos , Adulto , Giro Denteado/metabolismo , Giro Denteado/cirurgia , Epilepsia do Lobo Temporal/cirurgia , Feminino , Hipocampo/cirurgia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular , Masculino , Pessoa de Meia-Idade , Proteínas/metabolismo , Caracteres Sexuais , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz , Espectrometria de Massas em Tandem , Adulto Jovem
20.
Pathol Res Pract ; 209(5): 276-83, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23540296

RESUMO

Metastasis is a major cause of cancer recurrence or death. This study attempted to quantitatively identify different proteins in metastatic lung adenocarcinoma. The N/T quotient [number of metastatic lymph nodes (n)/tumor diameter (cm)] was used to select samples with an extreme metastatic phenotype. Among the six fresh frozen lung adenocarcinoma specimens, the three showing the highest N/T quotient represented the metastatic group, and others with the greatest tumor diameters without metastasis represented the non-metastatic group. After 2-dimensional electrophoresis, the significantly different protein spots were selected by image analysis and analyzed with MALDI-TOF mass spectrometry. Acyl-CoA thioesterase 8 isoform c (ACOT8) was one of most overexpressed proteins in the metastatic group, and it was validated by Western blot and immunohistochemical staining on 108 paraffin-embedded tumor samples. High ACOT8 expression was correlated with lymph node metastasis (p=0.002), recurrence (p=0.034), predominant histologic subtypes (p=0.007), and higher stage (p=0.005). In multivariate analysis, high ACOT8 expression was significantly associated with increased risks of lymph node metastasis (p=0.009) and cancer-related death (p=0.030), independent of clinical factors. ACOT8 may be a candidate prognostic biomarker and therapeutic target of lung adenocarcinoma.


Assuntos
Adenocarcinoma/secundário , Neoplasias Pulmonares/patologia , Proteínas de Neoplasias/metabolismo , Palmitoil-CoA Hidrolase/metabolismo , Adenocarcinoma/enzimologia , Adenocarcinoma/mortalidade , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores Tumorais/metabolismo , Eletroforese em Gel Bidimensional/métodos , Feminino , Secções Congeladas , Humanos , Processamento de Imagem Assistida por Computador , Estimativa de Kaplan-Meier , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/mortalidade , Linfonodos/patologia , Metástase Linfática , Masculino , Pessoa de Meia-Idade , Recidiva Local de Neoplasia/enzimologia , Recidiva Local de Neoplasia/mortalidade , Recidiva Local de Neoplasia/patologia , Estadiamento de Neoplasias , República da Coreia/epidemiologia , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Taxa de Sobrevida
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