Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 147
Filtrar
1.
Nat Neurosci ; 27(1): 34-47, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37996528

RESUMO

The mRNA transcript of the human STMN2 gene, encoding for stathmin-2 protein (also called SCG10), is profoundly impacted by TAR DNA-binding protein 43 (TDP-43) loss of function. The latter is a hallmark of several neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS). Using a combination of approaches, including transient antisense oligonucleotide-mediated suppression, sustained shRNA-induced depletion in aging mice, and germline deletion, we show that stathmin-2 has an important role in the establishment and maintenance of neurofilament-dependent axoplasmic organization that is critical for preserving the caliber and conduction velocity of myelinated large-diameter axons. Persistent stathmin-2 loss in adult mice results in pathologies found in ALS, including reduced interneurofilament spacing, axonal caliber collapse that drives tearing within outer myelin layers, diminished conduction velocity, progressive motor and sensory deficits, and muscle denervation. These findings reinforce restoration of stathmin-2 as an attractive therapeutic approach for ALS and other TDP-43-dependent neurodegenerative diseases.


Assuntos
Esclerose Lateral Amiotrófica , Animais , Camundongos , Esclerose Lateral Amiotrófica/metabolismo , Axônios/fisiologia , Denervação , Proteínas de Ligação a DNA/genética , Filamentos Intermediários/metabolismo , Filamentos Intermediários/patologia , Neurônios Motores/metabolismo , Estatmina/genética , Estatmina/metabolismo
2.
J Exp Clin Cancer Res ; 42(1): 317, 2023 Nov 27.
Artigo em Inglês | MEDLINE | ID: mdl-38008717

RESUMO

BACKGROUND: BRAF-mutant melanoma patients benefit from the combinatorial treatments with BRAF and MEK inhibitors. However, acquired drug resistance strongly limits the efficacy of these targeted therapies in time. Recently, many findings have underscored the involvement of microRNAs as main drivers of drug resistance. In this context, we previously identified a subset of oncomiRs strongly up-regulated in drug-resistant melanomas. In this work, we shed light on the molecular role of two as yet poorly characterized oncomiRs, miR-4443 and miR-4488. METHODS: Invasion and migration have been determined by wound healing, transwell migration/invasion assays and Real Time Cell Analysis (RTCA) technology. miR-4488 and miR-4443 have been measured by qRT-PCR. Nestin levels have been tested by western blot, confocal immunofluorescence, immunohistochemical and flow cytometry analyses. RESULTS: We demonstrate that the two oncomiRs are responsible for the enhanced migratory and invasive phenotypes, that are a hallmark of drug resistant melanoma cells. Moreover, miR-4443 and miR-4488 promote an aberrant cytoskeletal reorganization witnessed by the increased number of stress fibers and cellular protrusions-like cancer cell invadopodia. Mechanistically, we identified the intermediate filament nestin as a molecular target of both oncomiRs. Finally, we have shown that nestin levels are able to predict response to treatments in melanoma patients. CONCLUSIONS: Altogether these findings have profound translational implications in the attempt i) to develop miRNA-targeting therapies to mitigate the metastatic phenotypes of BRAF-mutant melanomas and ii) to identify novel biomarkers able to guide clinical decisions.


Assuntos
Melanoma , MicroRNAs , Humanos , Linhagem Celular Tumoral , Movimento Celular , Proliferação de Células , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Filamentos Intermediários/metabolismo , Filamentos Intermediários/patologia , Melanoma/tratamento farmacológico , Melanoma/genética , Melanoma/patologia , MicroRNAs/metabolismo , Nestina/genética , Nestina/metabolismo , Fenótipo , Proteínas Proto-Oncogênicas B-raf/genética , Proteínas Proto-Oncogênicas B-raf/metabolismo
3.
Cell Rep ; 42(12): 113470, 2023 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-37979166

RESUMO

Epithelial-mesenchymal transition (EMT) empowers epithelial cells with mesenchymal and stem-like attributes, facilitating metastasis, a leading cause of cancer-related mortality. Hybrid epithelial-mesenchymal (E/M) cells, retaining both epithelial and mesenchymal traits, exhibit heightened metastatic potential and stemness. The mesenchymal intermediate filament, vimentin, is upregulated during EMT, enhancing the resilience and invasiveness of carcinoma cells. The phosphorylation of vimentin is critical to its structure and function. Here, we identify that stabilizing vimentin phosphorylation at serine 56 induces multinucleation, specifically in hybrid E/M cells with stemness properties but not epithelial or mesenchymal cells. Cancer stem-like cells are especially susceptible to vimentin-induced multinucleation relative to differentiated cells, leading to a reduction in self-renewal and stemness. As a result, vimentin-induced multinucleation leads to sustained inhibition of stemness properties, tumor initiation, and metastasis. These observations indicate that a single, targetable phosphorylation event in vimentin is critical for stemness and metastasis in carcinomas with hybrid E/M properties.


Assuntos
Carcinoma , Filamentos Intermediários , Humanos , Vimentina/metabolismo , Fosforilação , Filamentos Intermediários/metabolismo , Filamentos Intermediários/patologia , Carcinoma/patologia , Células Epiteliais/metabolismo , Transição Epitelial-Mesenquimal , Células-Tronco Neoplásicas/metabolismo , Linhagem Celular Tumoral , Metástase Neoplásica/patologia
4.
Acta Neuropathol Commun ; 11(1): 109, 2023 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-37415197

RESUMO

Frontotemporal lobar degeneration (FTLD) is a group of disorders characterized by degeneration of the frontal and temporal lobes, leading to progressive decline in language, behavior, and motor function. FTLD can be further subdivided into three main subtypes, FTLD-tau, FTLD-TDP and FTLD-FUS based which of the three major proteins - tau, TDP-43 or FUS - forms pathological inclusions in neurons and glia. In this report, we describe an 87-year-old woman with a 7-year history of cognitive decline, hand tremor and gait problems, who was thought to have Alzheimer's disease. At autopsy, histopathological analysis revealed severe neuronal loss, gliosis and spongiosis in the medial temporal lobe, orbitofrontal cortex, cingulate gyrus, amygdala, basal forebrain, nucleus accumbens, caudate nucleus and anteromedial thalamus. Tau immunohistochemistry showed numerous argyrophilic grains, pretangles, thorn-shaped astrocytes, and ballooned neurons in the amygdala, hippocampus, parahippocampal gyrus, anteromedial thalamus, insular cortex, superior temporal gyrus and cingulate gyrus, consistent with diffuse argyrophilic grain disease (AGD). TDP-43 pathology in the form of small, dense, rounded neuronal cytoplasmic inclusion with few short dystrophic neurites was observed in the limbic regions, superior temporal gyrus, striatum and midbrain. No neuronal intranuclear inclusion was observed. Additionally, FUS-positive inclusions were observed in the dentate gyrus. Compact, eosinophilic intranuclear inclusions, so-called "cherry spots," that were visible on histologic stains were immunopositive for α-internexin. Taken together, the patient had a mixed neurodegenerative disease with features of diffuse AGD, TDP-43 proteinopathy and neuronal intermediate filament inclusion disease. She met criteria for three subtypes of FTLD: FTLD-tau, FTLD-TDP and FTLD-FUS. Her amnestic symptoms that were suggestive of Alzheimer's type dementia are best explained by diffuse AGD and medial temporal TDP-43 proteinopathy, and her motor symptoms were likely explained by neuronal loss and gliosis due to tau pathology in the substantia nigra. This case underscores the importance of considering multiple proteinopathies in the diagnosis of neurodegenerative diseases.


Assuntos
Doença de Alzheimer , Demência Frontotemporal , Degeneração Lobar Frontotemporal , Doenças Neurodegenerativas , Proteinopatias TDP-43 , Humanos , Feminino , Idoso de 80 Anos ou mais , Filamentos Intermediários/metabolismo , Filamentos Intermediários/patologia , Gliose , Degeneração Lobar Frontotemporal/patologia , Proteínas tau/metabolismo , Corpos de Inclusão Intranuclear/patologia , Proteínas de Ligação a DNA/metabolismo , Proteína FUS de Ligação a RNA
5.
Mol Cell Biochem ; 478(11): 2435-2444, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36807844

RESUMO

Vimentin is a main type 3 intermediate filament protein. It seems that abnormal expression of vimentin is contributed to the appearance of the aggressive feature of cancer cells. So that it has been reported that malignancy and epithelial-mesenchymal transition in solid tumors, and poor clinical outcomes in patients with lymphocytic leukemia and acute myelocytic leukemia have been associated with the high expression of vimentin. Vimentin is a non-caspase substrate of caspase-9 although its cleavage by caspase-9 in biological processes has not been reported. In the present study, we sought to understand whether vimentin cleavage mediated by caspase-9 could reverse the malignancy in leukemic cells. Herein, to address the issue, we investigated vimentin changes in differentiation and took advantage of the inducible caspase-9 (iC9)/AP1903 system in human leukemic NB4 cells. Following the transfection and treatment of the cells using the iC9/AP1903 system, vimentin expression, cleavage, and subsequently, the cell invasion and the relevant markers such as CD44 and MMP-9 were evaluated. Our results revealed the downregulation and cleavage of vimentin which attenuates the malignant phenotype of the NB4 cells. Considering the favorable effect of this strategy in keeping down the malignant features of the leukemic cells, the effect of the iC9/AP1903 system in combination with all-trans-retinoic acid (ATRA) treatment was evaluated. The obtained data prove that iC9/AP1903 significantly makes the leukemic cells more sensitive to ATRA.


Assuntos
Antineoplásicos , Leucemia Promielocítica Aguda , Humanos , Antineoplásicos/farmacologia , Caspase 9/metabolismo , Diferenciação Celular , Filamentos Intermediários/metabolismo , Filamentos Intermediários/patologia , Leucemia Promielocítica Aguda/tratamento farmacológico , Compostos Orgânicos , Tretinoína/farmacologia , Células Tumorais Cultivadas , Vimentina/metabolismo
6.
Vet Res ; 54(1): 7, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717839

RESUMO

Streptococcus suis serotype 2 (SS2) frequently colonizes the swine upper respiratory tract and can cause Streptococcal disease in swine with clinical manifestations of pneumonia, meningitis, and septicemia. Previously, we have shown that vimentin, a kind of intermediate filament protein, is involved in the penetration of SS2 through the tracheal epithelial barrier. The initiation of invasive disease is closely related to SS2-induced excessive local inflammation; however, the role of vimentin in airway epithelial inflammation remains unclear. Here, we show that vimentin deficient mice exhibit attenuated lung injury, diminished production of proinflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), and the IL-8 homolog, keratinocyte-derived chemokine (KC), and substantially reduced neutrophils in the lungs following intranasal infection with SS2. We also found that swine tracheal epithelial cells (STEC) without vimentin show decreased transcription of IL-6, TNF-α, and IL-8. SS2 infection caused reassembly of vimentin in STEC, and pharmacological disruption of vimentin filaments prevented the transcription of those proinflammatory cytokines. Furthermore, deficiency of vimentin failed to increase the transcription of nucleotide oligomerization domain protein 2 (NOD2), which is known to interact with vimentin, and the phosphorylation of NF-κB protein p65. This study provides insights into how vimentin promotes excessive airway inflammation, thereby exacerbating airway injury and SS2-induced systemic infection.


Assuntos
Infecções Estreptocócicas , Streptococcus suis , Doenças dos Suínos , Animais , Camundongos , Citocinas/genética , Epitélio/patologia , Inflamação/veterinária , Interleucina-6 , Interleucina-8 , Filamentos Intermediários/patologia , Infiltração de Neutrófilos , Sorogrupo , Infecções Estreptocócicas/veterinária , Infecções Estreptocócicas/patologia , Suínos , Traqueia/patologia , Fator de Necrose Tumoral alfa , Vimentina/genética
7.
Artigo em Inglês | MEDLINE | ID: mdl-35241571

RESUMO

BACKGROUND AND OBJECTIVES: To investigate whether white matter lesion activity, acute axonal damage, and axonal density in MS associate with CSF neurofilament light chain (NfL) levels. METHODS: Of 101 brain donors with MS (n = 92 progressive MS, n = 9 relapsing-remitting MS), ventricular CSF was collected, and NfL levels were measured. White matter lesions were classified as active, mixed, inactive, or remyelinated, and microglia/macrophage morphology in active and mixed lesions was classified as ramified, ameboid, or foamy. In addition, axonal density and acute axonal damage were assessed using Bielschowsky and amyloid precursor protein (APP) (immune)histochemistry. RESULTS: CSF NfL measurements of donors with recent (<1 year) or clinically silent stroke were excluded. CSF NfL levels correlated negatively with disease duration (p = 6.9e-3, r = 0.31). In donors without atrophy, CSF NfL levels correlated positively with the proportion of active and mixed lesions containing foamy microglia/macrophages (p = 9.85e-10 and p = 1.75e-3, respectively), but not with those containing ramified microglia. CSF NfL correlated negatively with proportions of inactive (p = 5.66e-3) and remyelinated lesions (p = 0.03). In the normal appearing pyramid tract, axonal density negatively correlated with CSF NfL levels (Bielschowsky, p = 0.02, r = -0.31), and the presence of acute axonal damage in lesions was related to higher NfL levels (APP, p = 1.17e-6). The amount of acute axonal damage was higher in active lesions with foamy microglia/macrophages and in the rim of mixed lesions with foamy microglia/macrophages when compared with active lesions containing ramified microglia/macrophages (p = 4.6e-3 and p = 0.02, respectively), the center and border of mixed lesions containing ramified microglia/macrophages (center: p = 4.6e-3, border, p = 4.6e-3, and n.s., p = 4.6e-3, respectively), the center of mixed lesions containing foamy microglia/macrophages (p = 4.6e-3 and p = 0.02, respectively), inactive lesions (p = 4.6e-3 and p = 4.6e-3, respectively), and remyelinated lesions (p = 0.03 and p = 0.04, respectively). DISCUSSION: Our results demonstrated that active and mixed white matter MS lesions with foamy microglia show high acute axonal damage and correlate with elevated CSF NfL levels. Our data support the use of this biomarker to monitor inflammatory demyelinating lesion activity with axonal damage in MS.


Assuntos
Esclerose Múltipla , Substância Branca , Axônios/patologia , Humanos , Filamentos Intermediários/patologia , Macrófagos/patologia , Substância Branca/patologia
8.
Brain Behav ; 12(2): e2494, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35084124

RESUMO

OBJECTIVE: To determine whether serum neurofilament light chain (sNfL) levels are suppressed in patients with the clinically isolated syndrome (CIS) following narrowband ultraviolet B phototherapy (UVB-PT). METHODS: sNfL levels were measured using a sensitive single-molecule array assay at baseline and up to 12 months in 17 patients with CIS, 10 of whom received UVB-PT, and were compared with healthy control (HC) and early relapsing remitting multiple sclerosis (RRMS) group. sNfL levels were correlated with magnetic resonance imaging total lesion volume (LV) determined using icobrain version 4.4.1 and with clinical outcomes. RESULTS: Baseline median sNfL levels were significantly higher in the CIS (20.6 pg/mL, interquartile range [IQR] 13.7-161.4) and RRMS groups (36.6 pg/ml [IQR] 16.2-212.2) than in HC (10.7 pg/ml [IQR] 4.9-21.5) (p = .012 and p = .0002, respectively), and were strongly correlated with T2 and T1 LV at 12 months (r = .800; p = .014 and r = .833; p = .008, respectively) in the CIS group. Analysis of changes in sNfL levels over time in the CIS group showed a significant cumulative suppressive effect of UVB-PT in the first 3 months (UVB-PT -10.6% vs non-UVB-PT +58.3%; p = .04) following which the levels in the two groups converged and continued to fall. CONCLUSIONS: Our findings provide the basis for further studies to determine the utility of sNfL levels as a marker of neuro-axonal damage in CIS and early MS and for assessing the efficacy of new therapeutic interventions such as UVB-PT.


Assuntos
Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Axônios/patologia , Biomarcadores , Humanos , Filamentos Intermediários/patologia , Esclerose Múltipla/patologia , Esclerose Múltipla Recidivante-Remitente/diagnóstico por imagem , Esclerose Múltipla Recidivante-Remitente/radioterapia , Fototerapia
9.
Int J Mol Sci ; 22(22)2021 Nov 18.
Artigo em Inglês | MEDLINE | ID: mdl-34830328

RESUMO

Epidermolysis bullosa simplex (EBS) is a group of inherited keratinopathies that, in most cases, arise due to mutations in keratins and lead to intraepidermal ruptures. The cellular pathology of most EBS subtypes is associated with the fragility of the intermediate filament network, cytolysis of the basal layer of the epidermis, or attenuation of hemidesmosomal/desmosomal components. Mutations in keratins 5/14 or in other genes that encode associated proteins induce structural disarrangements of different strengths depending on their locations in the genes. Keratin aggregates display impaired dynamics of assembly and diminished solubility and appear to be the trigger for endoplasmic reticulum (ER) stress upon being phosphorylated by MAPKs. Global changes in cellular signaling mainly occur in cases of severe dominant EBS mutations. The spectrum of changes initiated by phosphorylation includes the inhibition of proteasome degradation, TNF-α signaling activation, deregulated proliferation, abnormal cell migration, and impaired adherence of keratinocytes. ER stress also leads to the release of proinflammatory danger-associated molecular pattern (DAMP) molecules, which enhance avalanche-like inflammation. Many instances of positive feedback in the course of cellular stress and the development of sterile inflammation led to systemic chronic inflammation in EBS. This highlights the role of keratin in the maintenance of epidermal and immune homeostasis.


Assuntos
Alarminas/genética , Epiderme/metabolismo , Epidermólise Bolhosa Simples/genética , Queratina-14/genética , Queratina-5/genética , Queratinócitos/metabolismo , Alarminas/metabolismo , Estresse do Retículo Endoplasmático/genética , Epiderme/patologia , Epidermólise Bolhosa Simples/metabolismo , Epidermólise Bolhosa Simples/patologia , Regulação da Expressão Gênica , Humanos , Inflamação , Filamentos Intermediários/metabolismo , Filamentos Intermediários/patologia , Filamentos Intermediários/ultraestrutura , Queratina-14/metabolismo , Queratina-5/metabolismo , Queratinócitos/patologia , Proteínas Quinases Ativadas por Mitógeno/genética , Proteínas Quinases Ativadas por Mitógeno/metabolismo , Mutação , Complexo de Endopeptidases do Proteassoma/metabolismo , Agregados Proteicos , Proteólise , Transdução de Sinais , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
10.
J Gynecol Obstet Hum Reprod ; 50(3): 101761, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-32325268

RESUMO

OBJECTIVE: To identify the risk factors associated with dysmenorrhea in adenomyosis and to discuss the potential hormone-based understanding of pain mechanisms. STUDY DESIGN: Adenomyosis patients with mild or no dysmenorrhea (n = 40, Group 1) and moderate-to-severe dysmenorrhea (n = 80, Group 2) were recruited. Charts of all patients were recorded. An immunohistochemistry (IHC) analysis was performed to detect the cellular levels of estrogen receptor-α (ER-α), estrogen receptor-ß (ER-ß), gonadotropin-releasing hormone receptor (GnRH-R), and neurofilaments (NFs) in 60 cases. RESULTS: A history of cesarean section (CS) was positively related to the degree of dysmenorrhea in adenomyosis (OR (95 % CI): 4.397 (1.371-14.104)). The ER-α levels in the eutopic endometrium (EUE) of Group 2 were higher than those in the ectopic endometrium (ECE) of Group 1. Group 2 had higher NF levels in the ECE than in the EUE. CONCLUSION: A history of CS is a risk factor for adenomyosis with moderate-to-severe dysmenorrhea. For patients with adenomyosis, high ER-α levels in the EUE and high NF levels in the ECE may be related to moderate-to-severe dysmenorrhea. These hormone-based mechanisms may contribute to our understanding of the pathogenesis of dysmenorrhea in adenomyosis.


Assuntos
Adenomiose/epidemiologia , Dismenorreia/epidemiologia , Adenomiose/etiologia , Adenomiose/metabolismo , Adulto , Cesárea/efeitos adversos , Cesárea/estatística & dados numéricos , Dismenorreia/etiologia , Endométrio/química , Endométrio/patologia , Receptor alfa de Estrogênio/análise , Receptor beta de Estrogênio/análise , Feminino , Humanos , Imuno-Histoquímica , Filamentos Intermediários/patologia , Pessoa de Meia-Idade , Gravidez , Receptores LHRH/análise , Fatores de Risco
11.
Am J Dermatopathol ; 42(12): 916-922, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32732692

RESUMO

Desmoplastic melanoma can be difficult to diagnose and on average have a significantly higher T stage at the time of diagnosis compared with conventional melanomas. Histologically, these tumors typically consist of spindle cells in a fibrous matrix. The spindle cells may display fibroblast and/or Schwann cell-like features. In this study, we describe the features of 12 cases of desmoplastic melanoma closely simulating neurofibroma. Although the spindle cells in these tumors may be indistinguishable from those of neurofibroma, features such as prominent fibroplasia (12/12), poor lateral circumscription (8/9), diffuse infiltration of subcutaneous tissue (7/9), and lymphoid aggregates (10/12) may be helpful clues to the diagnosis. No immunohistochemical markers were reliable in distinguishing neurofibroma-like desmoplastic melanomas from neurofibroma. Clinical follow-up was available in 8 cases, of which 4 were initially misdiagnosed as benign neoplasms and given no further re-excision. All 4 of these cases recurred; 2 of which showed transformation to a more aggressive phenotype.


Assuntos
Melanoma/patologia , Neurofibroma/patologia , Neoplasias Cutâneas/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Antígenos de Neoplasias/análise , Biomarcadores Tumorais/análise , Biópsia , Diagnóstico Diferencial , Erros de Diagnóstico , Feminino , Humanos , Illinois , Imuno-Histoquímica , Filamentos Intermediários/patologia , Masculino , Melanoma/química , Melanoma/cirurgia , Pessoa de Meia-Idade , Recidiva Local de Neoplasia , Neurofibroma/química , Neurofibroma/cirurgia , Cidade de Nova Iorque , Fenótipo , Valor Preditivo dos Testes , Neoplasias Cutâneas/química , Neoplasias Cutâneas/cirurgia , Fatores de Tempo , Resultado do Tratamento , Proteína Supressora de Tumor p53/análise
12.
FEBS J ; 287(24): 5304-5322, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-32255262

RESUMO

Vimentin intermediate filaments are a significant component of the cytoskeleton in cells of mesenchymal origin. In vivo, filaments assemble and disassemble and thus participate in the dynamic processes of the cell. Post-translational modifications (PTMs) such as protein phosphorylation regulate the multiphasic association of vimentin from soluble complexes to insoluble filaments and the reverse processes. The thiol side chain of the single vimentin cysteine at position 328 (Cys328) is a direct target of oxidative modifications inside cells. Here, we used atomic force microscopy, electron microscopy and a novel hydrogen-deuterium exchange mass spectrometry (HDex-MS) procedure to investigate the structural consequences of S-nitrosylation and S-glutathionylation of Cys328 for in vitro oligomerisation of human vimentin. Neither modification affects the lateral association of tetramers to unit-length filaments (ULF). However, S-glutathionylation of Cys328 blocks the longitudinal assembly of ULF into extended filaments. S-nitrosylation of Cys328 does not hinder but slows down the elongation. Likewise, S-glutathionylation of preformed vimentin filaments causes their extensive fragmentation to smaller oligomeric species. Chemical reduction of the S-glutathionylated Cys328 thiols induces reassembly of the small fragments into extended filaments. In conclusion, our in vitro results suggest S-glutathionylation as a candidate PTM for an efficient molecular switch in the dynamic rearrangements of vimentin intermediate filaments, observed in vivo, in response to changes in cellular redox status. Finally, we demonstrate that HDex-MS is a powerful method for probing the kinetics of vimentin filament formation and filament disassembly induced by PTMs.


Assuntos
Cisteína/metabolismo , Citoesqueleto/patologia , Glutationa/metabolismo , Filamentos Intermediários/patologia , Processamento de Proteína Pós-Traducional , Vimentina/química , Vimentina/metabolismo , Cisteína/química , Citoesqueleto/metabolismo , Glutationa/química , Humanos , Técnicas In Vitro , Filamentos Intermediários/metabolismo , Cinética , Oxirredução , Fosforilação , Multimerização Proteica
13.
Int J Mol Sci ; 20(9)2019 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-31075828

RESUMO

Despite the different antineoplastic mechanisms of action, peripheral neurotoxicity induced by all chemotherapy drugs (anti-tubulin agents, platinum compounds, proteasome inhibitors, thalidomide) is associated with neuron morphological changes ascribable to cytoskeleton modifications. The "dying back" degeneration of distal terminals (sensory nerves) of dorsal root ganglia sensory neurons, observed in animal models, in in vitro cultures and biopsies of patients is the most evident hallmark of the perturbation of the cytoskeleton. On the other hand, in highly polarized cells like neurons, the cytoskeleton carries out its role not only in axons but also has a fundamental role in dendrite plasticity and in the organization of soma. In the literature, there are many studies focused on the antineoplastic-induced alteration of microtubule organization (and consequently, fast axonal transport defects) while very few studies have investigated the effect of the different classes of drugs on microfilaments, intermediate filaments and associated proteins. Therefore, in this review, we will focus on: (1) Highlighting the fundamental role of the crosstalk among the three filamentous subsystems and (2) investigating pivotal cytoskeleton-associated proteins.


Assuntos
Citoesqueleto/patologia , Tratamento Farmacológico , Doenças do Sistema Nervoso Periférico/induzido quimicamente , Doenças do Sistema Nervoso Periférico/patologia , Animais , Modelos Animais de Doenças , Humanos , Filamentos Intermediários/patologia , Neurônios/patologia
14.
Mater Sci Eng C Mater Biol Appl ; 96: 616-624, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-30606573

RESUMO

Intermediate filaments, together with actin microfilaments and microtubules constituent the cytoskeleton of mammalian cells, involving in various cellular activities. The roles of intermediate filaments in cell skeleton reorganization when responding with extracellular matrix (ECM) nanostructure are poorly understood yet. To unveil the effects of fibrous composition and orientation on cells, we developed electrospun nanofibers of varying topology and components, and the effects on assembly of intermediate filaments as keratin and vimentin were investigated in detail. We found that aligned nanofibers enhanced expression of E-cadherin and promoted assembly of keratin intermediate filaments. Meanwhile, the compositional variation show different preference on up-regulation of the two intermediate filaments. Compared to keratin, the assembly of vimentin intermediate filaments were promoted by incorporating bovine serum albumin (BSA) functionalized graphene oxide (BSA-GO) into polycaprolactone (PCL) nanofibers. Thus, our findings elucidate how the different physical factors of fibrous extracellular matrix affect the reorganization of cytoskeleton by assembly of keratin and vimentin intermediate filaments.


Assuntos
Matriz Extracelular/química , Filamentos Intermediários/metabolismo , Queratinas/metabolismo , Nanofibras/química , Proteínas de Neoplasias/metabolismo , Neoplasias Pancreáticas/metabolismo , Vimentina/metabolismo , Linhagem Celular Tumoral , Humanos , Filamentos Intermediários/patologia , Neoplasias Pancreáticas/patologia , Neoplasias Pancreáticas
15.
J Cell Physiol ; 234(4): 3458-3468, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-30368811

RESUMO

Notochordal cells (NCs), characterized by their vacuolated morphology and coexpression of cytokeratin and vimentin intermediate filaments (IFs), form the immature nucleus pulposus (NP) of the intervertebral disc. As humans age, NCs give way to mature NP cells, which do not possess a vacuolated morphology and typically only express vimentin IFs. In light of their concomitant loss, we investigated the relationship between cytosolic vacuoles and cytokeratin IFs, specifically those containing cytokeratin-8 proteins, using a human chordoma cell line as a model for NCs. We demonstrate that the chemical disruption of IFs with acrylamide, F-actin with cytochalasin-D, and microtubules with nocodazole all result in a significant (p < 0.001) decrease in vacuolation. However, vacuole loss was the greatest in acrylamide-treated cells. Examination of the individual roles of vimentin and cytokeratin-8 IFs in the existence of vacuoles was accomplished using small interfering RNA-mediated RNA interference to knock down either vimentin or cytokeratin-8 expression. Reduction of cytokeratin-8 expression was associated with a less-vacuolated cell morphology. These data demonstrate that cytokeratin-8 IFs are involved in stabilizing vacuoles and that their diminished expression could play a role in the loss of vacuolation in NCs during aging. A better understanding of the NCs may assist in preservation of this cell type for NP maintenance and regeneration.


Assuntos
Cordoma/metabolismo , Filamentos Intermediários/metabolismo , Queratina-8/metabolismo , Notocorda/metabolismo , Vacúolos/metabolismo , Acrilamida/toxicidade , Linhagem Celular Tumoral , Cordoma/patologia , Citocalasina D/toxicidade , Humanos , Filamentos Intermediários/efeitos dos fármacos , Filamentos Intermediários/genética , Filamentos Intermediários/patologia , Queratina-8/genética , Nocodazol/toxicidade , Notocorda/efeitos dos fármacos , Notocorda/patologia , Transdução de Sinais , Vacúolos/efeitos dos fármacos , Vacúolos/patologia
16.
Clin Neuropathol ; 37(5): 239-244, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29956645

RESUMO

AIMS: To characterize the topography of white matter pathology in neuronal intermediate filament inclusion disease (NIFID), a rare subtype of frontotemporal lobar degeneration (FTLD) with "fused in sarcoma" (FUS)-immunoreactive inclusions. MATERIAL AND METHODS: Fiber tracts from frontal and temporal lobes of 10 cases of NIFID. METHOD: Spatial patterns of the vacuolation, glial cell nuclei, and glial inclusions (GI) were studied across cortical fiber tracts from each case. RESULTS: Vacuoles and glial cells in NIFID were distributed either in regularly-distributed clusters or in large diffuse clusters contrasting with typical control cases in which smaller clusters of glial cells were surrounded by more compact clusters of vacuoles. Axonal varicosities and GI were also observed in the precentral gyrus (PCG) of 4 NIFID cases. Depending on region, the densities of glial cells and vacuoles were either positively or negatively spatially correlated, but there were no spatial correlations between the densities of the GI and either the vacuoles or glial cells. Spatial patterns in white matter were similar to those reported in adjacent gray matter. CONCLUSION: 1) Pathological changes across the white matter in NIFID are topographically distributed, 2) there is a correlation between the development of vacuolation and gliosis, and 3) white matter and gray matter pathologies are closely related.
.


Assuntos
Infecções por Citomegalovirus/patologia , Degeneração Lobar Frontotemporal/patologia , Filamentos Intermediários/patologia , Substância Branca/patologia , Adulto , Idade de Início , Encéfalo/patologia , Feminino , Substância Cinzenta/patologia , Humanos , Corpos de Inclusão/patologia , Masculino , Pessoa de Meia-Idade , Fibras Nervosas/patologia , Neuroglia/patologia , Vacúolos/patologia , Adulto Jovem
17.
Am J Physiol Renal Physiol ; 315(4): F769-F780, 2018 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-29631355

RESUMO

Most renal transplants ultimately fail secondary to chronic allograft nephropathy (CAN). Vimentin (vim) is a member of the intermediate filament family of proteins and has been shown to be important in the development of CAN. One of the pathways leading to chronic renal fibrosis after transplant is thought to be epithelial to mesenchymal transition (EMT). Even though vim expression is one of the main steps of EMT, it is unknown whether vim expression is required for EMT leading to renal fibrosis and allograft loss. To this end, the role of vim in renal fibrosis was determined via unilateral ureteral obstruction (UUO) in vim knockout mice (129 svs6 vim -/-). Following UUO, kidneys were recovered and analyzed via Western blotting, immunofluorescence, and transcriptomics. Cultured human proximal renal tubular (HK-2) cells were subjected to lentiviral-driven inhibition of vim expression and then treated with transforming growth factor (TGF)-ß to undergo EMT. Immunoblotting as well as wound healing assays were used to determine development of EMT. Western blotting analyses of mice undergoing UUO reveal increased levels of vim soon after UUO. As expected, interstitial collagen deposition increased in control mice following UUO but decreased in vim -/- kidneys. Immunofluorescence analyses also revealed altered localization of ß-catenin in vim -/- mice undergoing UUO without significant changes in mRNA levels. However, RNA sequencing revealed a decrease in ß-catenin-dependent genes in vim -/- kidneys. Finally, vim-silenced HK-2 cell lines undergoing EMT were shown to have decreased cellular migration during wound healing. We conclude that vim inhibition decreases fibrosis following UUO by possibly altering ß-catenin localization and downstream signaling.


Assuntos
Fibrose/patologia , Obstrução Ureteral/metabolismo , Obstrução Ureteral/patologia , Vimentina/metabolismo , Animais , Modelos Animais de Doenças , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Transição Epitelial-Mesenquimal/fisiologia , Fibrose/metabolismo , Filamentos Intermediários/metabolismo , Filamentos Intermediários/patologia , Camundongos Knockout , Transdução de Sinais/fisiologia , Sistema Urinário/metabolismo , Sistema Urinário/patologia
19.
Brain Tumor Pathol ; 34(4): 172-178, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28799062

RESUMO

The term "long-term epilepsy-associated tumor (LEAT)" encompasses brain lesions associated with drug-resistant epilepsy over a long duration (≥2 years). Notably, some LEATs do not fit into any of the classifications of the World Health Organization (WHO). Herein, we report a LEAT that occurred in the left amygdala of a 16-year-old patient with intractable epilepsy. Histological examination of the resected amygdala revealed diffusely infiltrating tumor cells in the cortex. Perineuronal satellitosis and perivascular aggregation of tumor cells were apparent, along with mild nuclear enlargement and cytologic atypia. Tumor cells were positive for oligodendrocyte transcription factor 2 and neuronal markers including NeuN, neurofilaments, and synaptophysin, but were negative for CD34 and nestin. The most intriguing finding was intranuclear filaments, which appeared as rod- or needle-like shapes under high-power view. Ancillary ultrastructural analysis revealed thin filamentous intranuclear structures in tumor cells. Based on the glioneuronal nature of these cells as well as the infiltrative growth pattern, a diagnosis of LEAT was rendered that was deemed WHO grade I to II; however, the clinicopathological implications of the intranuclear inclusions remain unknown. The patient is currently alive and well without seizures.


Assuntos
Tonsila do Cerebelo/patologia , Neoplasias Encefálicas/complicações , Neoplasias Encefálicas/patologia , Epilepsia/etiologia , Filamentos Intermediários/patologia , Corpos de Inclusão Intranuclear/patologia , Adolescente , Tonsila do Cerebelo/citologia , Antígenos Nucleares/metabolismo , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/metabolismo , Humanos , Filamentos Intermediários/ultraestrutura , Masculino , Proteínas do Tecido Nervoso/metabolismo , Fator de Transcrição 2 de Oligodendrócitos/metabolismo , Sinaptofisina/metabolismo , Fatores de Tempo
20.
Mol Med Rep ; 16(2): 1661-1668, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28656221

RESUMO

Spinal cord injury is a serious threat to human health and various techniques have been deployed to ameliorate or cure its effects. Stem cells transplantation is one of the promising methods. The primary aim of the present study was to investigate the effect of the transplantation of olfactory ensheathing cell (OEC) conditioned medium­induced bone marrow stromal cells (BMSCs) on spinal cord injury. Rat spinal cord compression injury animal models were generated, and the rats divided into the following three groups: Group A, (control) Dulbecco's modified Eagle's medium­treated group; group B, normal BMSC­treated group; group C, OEC conditioned medium­induced BMSC­treated group. The animals were sacrificed at 2, 4 and 8 weeks following transplantation for hematoxylin and eosin staining, and fluorescence staining of neurofilament protein, growth associated protein­43 and neuron­specific nuclear protein. The cavity area of the spinal cord injury was significantly reduced at 2 and 4 weeks following transplantation in group C, and a significant difference between the Basso, Beattie and Bresnahan score in group C and groups A and B was observed. Regenerated nerve fibers were observed in groups B and C; however, a greater number of regenerated nerve fibers were observed in group C. BMSCs induced by OEC conditioned medium survived in vivo, significantly reduced the cavity area of spinal cord injury, promoted nerve fiber regeneration following spinal cord injury and facilitated recovery of motor function. The present study demonstrated a novel method to repair spinal cord injury by using induced BMSCs, with satisfactory results.


Assuntos
Transplante de Células-Tronco Mesenquimais/métodos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Traumatismos da Medula Espinal/metabolismo , Traumatismos da Medula Espinal/terapia , Animais , Meios de Cultivo Condicionados , Imuno-Histoquímica , Filamentos Intermediários/patologia , Masculino , Modelos Animais , Atividade Motora/fisiologia , Regeneração Nervosa , Ratos , Ratos Sprague-Dawley , Recuperação de Função Fisiológica , Traumatismos da Medula Espinal/diagnóstico por imagem , Traumatismos da Medula Espinal/patologia , Cicatrização
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA