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1.
Cancers (Basel) ; 16(7)2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38610976

RESUMO

A subset of patients with rheumatoid arthritis receiving methotrexate develop immune deficiencies and dysregulation-associated lymphoproliferative disorders. Patients with these disorders often exhibit spontaneous regression after MTX withdrawal; however, chemotherapeutic intervention is frequently required in patients with classic Hodgkin lymphoma arising in immune deficiency/dysregulation. In this study, we examined PD-L1 expression levels and 9p24.1 copy number alterations in 27 patients with classic Hodgkin lymphoma arising from immune deficiency/dysregulation. All patients demonstrated PD-L1 protein expression and harbored 9p24.1 copy number alterations on the tumor cells. When comparing clinicopathological data and associations with 9p24.1 copy number features, the copy gain group showed a significantly higher incidence of extranodal lesions and clinical stages than the amplification group. Notably, all cases in the amplification group had latency type II, while 6/8 (75%) in the copy gain group had latency type II, and 2/8 (25%) had latency type I. Thus, a subset of the copy-gain group demonstrated more extensive extranodal lesions and higher clinical stages. This finding speculates the presence of a genetically distinct subgroup within the group of patients who develop immune deficiencies and dysregulation-associated lymphoproliferative disorders, which may explain certain characteristic features.

2.
Rapid Commun Mass Spectrom ; 37(24): e9649, 2023 Dec 30.
Artigo em Inglês | MEDLINE | ID: mdl-37953546

RESUMO

RATIONALE: The structures of metal complexes determine their stable functioning in product performance. Electrospray ionization mass spectrometry (ESI-MS) is used in studying metal complexes despite exhibiting limitations in analyzing labile complexes. Therefore, identifying a method for detecting unstable complexes and evaluating their stabilities is necessary, providing a theoretical basis for material selection and performance evaluation. METHODS: The standard complexes Zn(BTZ)2 , Fe(acac)3 , and Sn(Oct)2 were analyzed using nanoESI quadrupole orbitrap MS (nanoESI-MS) and compared with ESI-MS for two temperature modes. The three complexes and alkylamine-Ag+ complexes were analyzed using nanoESI and collision-induced dissociation MS/MS (CID-MS/MS). Breakdown plots of the survival yield against collision energies expressed in terms of the center-of-mass were constructed according to the obtained product ion spectra. Quantum chemical calculations based on density functional theory were performed to calculate the binding energies between the alkylamines and Ag+ . RESULTS: The three standard complexes were detected in the native structures using nanoESI-MS, confirming the advantage of nanoESI over ESI for detecting unstable complexes. The gas-phase stabilities of the amine-Ag+ complexes, estimated using the breakdown plots constructed by plotting the data obtained via nanoESI and CID-MS/MS, were consistent with the established theories, previous studies, and binding energies calculated using computational methods. CONCLUSIONS: NanoESI-MS is suitable for detecting labile complexes and enables the structural analyses of unknown complex additives. A novel approach based on nanoESI and CID-MS/MS was developed to determine the gas-phase stabilities of complexes, enabling their quantification and comparison and providing a technical basis for product improvement, which is essential in developing industrial materials.

3.
Blood Adv ; 7(24): 7459-7470, 2023 12 26.
Artigo em Inglês | MEDLINE | ID: mdl-37552496

RESUMO

The distribution and clinical impact of cell-of-origin (COO) subtypes of diffuse large B-cell lymphoma (DLBCL) outside Western countries remain unknown. Recent literature also suggests that there is an additional COO subtype associated with the germinal center dark zone (DZ) that warrants wider validation to generalize clinical relevance. Here, we assembled a cohort of Japanese patients with untreated DLBCL and determined the refined COO subtypes, which include the DZ signature (DZsig), using the NanoString DLBCL90 assay. To compare the distribution and clinical characteristics of the molecular subtypes, we used a data set from the cohort of British Columbia Cancer (BCC) (n = 804). Through the 1050 patient samples on which DLBCL90 assay was successfully performed in our cohort, 35%, 45%, and 6% of patients were identified to have germinal center B-cell-like (GCB) DLBCL, activated B-cell-like (ABC) DLBCL, and DZsig-positive (DZsigpos) DLBCL, respectively, with the highest prevalence of ABC-DLBCL, differing significantly from the BCC result (P < .001). GCB-DLBCL, ABC-DLBCL, and DZsigpos-DLBCL were associated with 2-year overall survival rates of 88%, 75%, and 66%, respectively (P < .0001), with patients with DZsigpos-DLBCL having the poorest prognosis. In contrast, GCB-DLBCL without DZsig showed excellent outcomes after rituximab-containing immunochemotherapy. DZsigpos-DLBCL was associated with the significant enrichment of tumors with CD10 expression, concurrent MYC/BCL2 expression, and depletion of microenvironmental components (all, P < .05). These results provide evidence of the distinct distribution of clinically relevant molecular subtypes in Japanese DLBCL and that refined COO, as measured by the DLBCL90 assay, is a robust prognostic biomarker that is consistent across geographical areas.


Assuntos
Linfoma Difuso de Grandes Células B , Humanos , Prognóstico , Japão/epidemiologia , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfócitos B/metabolismo , Rituximab/uso terapêutico
4.
J Clin Exp Hematop ; 63(2): 90-98, 2023 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-37245972

RESUMO

Epstein-Barr virus-positive mucocutaneous ulcer (EBVMCU) is a newly recognized disease entity characterized by EBV-positive atypical B-cell proliferation. EBVMCU is a localized self-limited disease that affects mucosa and skin, especially the oral cavity. EBVMCU develops in immunosuppressive patients, such as those with methotrexate (MTX)-administrated rheumatoid arthritis (RA). Here we clinicopathologically analyzed 12 EBVMCU patients in a single institution. All cases were administrated MTX for RA, and five cases occurred in the oral cavity. All cases except one had demonstrated spontaneous regression after withdrawal of the immunosuppressive agent. We found 4 of 5 cases in the oral cavity had preceding traumatic events in the same site within a week before the onset of EBVMCU. Although there is no detailed and large study that has analyzed the trigger of EBVMCU, a traumatic event would indeed be a significant trigger for EBVMCU in the oral cavity. The cases were histologically classified; six cases were diffuse large B-cell lymphoma-type, five were polymorphous-type, and one was Hodgkin-like lesion type due to morphological appearance and immunophenotype. The PD-L1 expression was also examined by two antibodies for PD-L1 (E1J2J and SP142). Both antibodies revealed identical results for PD-L1 expression, and three cases were positive for PD-L1. The application of SP142 for evaluating the immune status of lymphomagenesis has also been proposed. Nine of 12 cases were negative for PD-L1, which implies that most EBVMCU cases may be caused by an immunodeficiency, rather than an immune-evasion, mechanism. However, as three cases were positive for PD-L1, immune escape may underly the pathogenesis in a subset of EBVMCU cases.


Assuntos
Artrite Reumatoide , Infecções por Vírus Epstein-Barr , Humanos , Metotrexato/efeitos adversos , Infecções por Vírus Epstein-Barr/induzido quimicamente , Infecções por Vírus Epstein-Barr/complicações , Úlcera , Herpesvirus Humano 4/metabolismo , Antígeno B7-H1 , Imunossupressores/efeitos adversos , Artrite Reumatoide/tratamento farmacológico , Artrite Reumatoide/complicações
5.
Case Rep Dent ; 2022: 9592077, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36046849

RESUMO

Hematopoietic stem cell transplantation (HSCT) is a common method for patients such as hematologic malignancies. However, HSCT generally has a higher risk of secondary solid cancer development. The aim of this study was to emphasize the need for lifelong follow-up of oral secondary solid cancer. The patient was a male who underwent HSCT for chronic myelogenous leukaemia at the age of 31 years. He underwent ten onsets on oral secondary solid cancers during his subsequent follow-up of more than 20 years. In conclusion, patients after HSCT require lifelong observation of oral secondary solid cancer, which may be accompanied by repeated new and recurrent occurrences.

6.
Case Rep Dent ; 2022: 9098201, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35634459

RESUMO

Dialysis-related amyloidosis (DRA) represents a group of relatively rare disorders characterized by the systemic extracellular deposition of insoluble fibrils of amyloid protein in long-term dialysis patients. We describe herein a case of relatively early DRA on the tongue of a long-term dialysis patient. A 67-year-old man with a 39-year history of dialysis was referred for diagnosis of a tongue mass. On examination, a collection of whitish-yellow papules was identified on the ventral surface of the tongue tip. The pathological diagnosis was DRA. Clinicians should be aware that long-term dialysis can cause oral amyloidosis of the tongue.

7.
Mod Pathol ; 35(2): 177-185, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34404905

RESUMO

Next-generation sequencing of oral squamous cell carcinoma (OSCC) has revealed TP53 as the most frequently mutated gene in OSCC mutually exclusive with human papillomavirus infection. Oral epithelial dysplasia (OED) is defined as a precancerous lesion of OSCC by the current World Health Organization (WHO) classification; therefore, it is assumed that TP53 mutations occur in early precancerous conditions such as OED. Here, we conducted an integrated analysis of TP53, including whole coding sequencing of TP53, FISH analysis of the 17p13.1 locus, and immunohistochemical analysis for p53 (p53-IHC), in 40 OED cases. We detected 20 mutations in 16 (40%) OED cases, and four cases, each harbored two mutations. FISH analysis revealed six of 24 cases (25%) had a deletion on 17p13.1, and four cases had concurrent TP53 mutations and 17p13.1 deletion (2-hit). Also, the increased frequency of TP53 mutations in higher degrees of OED implies acquisition of the mutation is a major event toward OSCC. p53-IHC revealed that overall cases could be categorized into four patterns that correlate well with the mutational status of TP53. Especially, two patterns, broad p53 expression type (pattern HI) and p53 null type (pattern LS), strongly correlated with a missense mutation and nonsense mutation, respectively. Furthermore, seven of the 40 cases progressed to SCC, and six of these seven cases presented pattern HI or LS. Therefore, patterns HI and LS have a high risk for malignant transformation if excisional treatment is not performed irrespective of the dysplasia grade. Although the current WHO classification mainly focuses on morphological criteria for the diagnosis of OED, interobserver discrepancy appears in some instances of the OED diagnosis. Our immunohistochemical analysis supports a more accurate pathological diagnosis for OED in cases of low dysplastic changes or of differential diagnosis with non-dysplastic lesions.


Assuntos
Carcinoma de Células Escamosas , Neoplasias de Cabeça e Pescoço , Neoplasias Bucais , Biomarcadores Tumorais/análise , Carcinoma de Células Escamosas/patologia , Humanos , Imuno-Histoquímica , Neoplasias Bucais/genética , Neoplasias Bucais/metabolismo , Mutação , Coloração e Rotulagem , Proteína Supressora de Tumor p53/genética , Proteína Supressora de Tumor p53/metabolismo
8.
Rinsho Ketsueki ; 63(12): 1643-1647, 2022.
Artigo em Japonês | MEDLINE | ID: mdl-36653137

RESUMO

A 62-year-old woman was presented at our hospital with visual disturbance. An ocular examination revealed bilateral Roth spots. Laboratory data revealed leukocytosis (236,200 µl) with an excess blast (11%). Physical examination and computed tomography (CT) showed systemic lymphadenopathy. A bone marrow examination revealed a composition of 9.2% blast. Chromosomal analysis on bone marrow cells revealed 46,XX,t (3;12)(q26.2;p13),t (9;22)(q34.1;q11.2) in 80% of metaphases (16/20). Inguinal lymph node biopsy revealed diffuse proliferation of myeloperoxidase (MPO)-positive abnormal cells. Fluorescence in situ hybridization analysis was used to detect the BCR-ABL1 fusion gene and split the signals of MECOM and ETV6. She was diagnosed with de-novo chronic myeloid leukemia (CML) extramedullary blast crisis. She received tyrosine kinase inhibitor (TKI) combination chemotherapy and allogeneic hematopoietic stem cell transplantation and achieved a major molecular response. In this study, we reported a case of CML in blast-phase initially presenting as extramedullary, in which cytogenetic and molecular analyses were useful in the staging method.


Assuntos
Crise Blástica , Leucemia Mielogênica Crônica BCR-ABL Positiva , Feminino , Humanos , Pessoa de Meia-Idade , Crise Blástica/genética , Crise Blástica/patologia , Hibridização in Situ Fluorescente , Leucemia Mielogênica Crônica BCR-ABL Positiva/diagnóstico , Leucemia Mielogênica Crônica BCR-ABL Positiva/genética , Leucemia Mielogênica Crônica BCR-ABL Positiva/terapia , Análise Citogenética , Linfonodos/patologia
9.
Cancer Diagn Progn ; 1(5): 499-505, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35403155

RESUMO

Background: Laparoscopic surgery for malignant tumours occasionally results in recurrence at the trocar insertion site or port-site metastasis (PSM). We report on a patient requiring emergency laparoscopic surgery for an ovarian tumour with a review of the relevant literature. Case Report: A 42-year-old woman developed sudden abdominal pain and underwent laparoscopic right adnexectomy because of a suspected ovarian cystic tumour rupture. The postoperative histological diagnosis was a mucinous borderline ovarian tumour; however, an undifferentiated carcinoma was detected at the port site eight months after the initial surgery. The histopathological diagnosis of the abdominal wall tumour at the port site differed from intraoperative pathological findings, which was contradictory to PSM definition. Postoperatively, she received three systemic chemotherapy courses but died consequent to tumour metastasis. Conclusion: This is an atypical PSM case with histopathological differences from the initial tumour. Careful preoperative diagnosis and intraoperative attention are essential in such cases.

10.
Cancer Sci ; 111(2): 749-759, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31849147

RESUMO

The revised WHO classification newly defined the entities "High-grade B-cell lymphoma with MYC and BCL2, and/or BCL6 rearrangements (HGBL-DH/TH)" and "HGBL, NOS." Standard immunochemotherapy for diffuse large B-cell lymphoma (DLBCL), R-CHOP, is insufficient for HGBL patients, and there are currently no optimized therapeutic regimens for HGBL. We previously reported that CCND3, which encodes cyclin D3, harbored high mutation rates in Burkitt lymphoma (BL), HGBL and a subset of DLBCL. Furthermore, the knockdown of cyclin D3 expression was toxic to germinal center (GC)-derived B-cell lymphomas. Thus, the fundamental function of cyclin D3 is important for the pathogenesis of GC-derived B-cell lymphoma. We herein used two structurally different CDK4/6 inhibitors, palbociclib and abemaciclib, and examined their suppressive effects on cell proliferation and their ability to induce apoptosis in various aggressive B-cell lymphoma cell lines. The results obtained demonstrated that abemaciclib more strongly suppressed cell proliferation and induced apoptosis in GC-derived B-cell lymphoma cell lines than the control, but only slightly inhibited those features in activated B-cell (ABC)-like DLBCL cell lines. Palbociclib exerted partial or incomplete effects compared with the control and the effect was intermediate between abemaciclib and the control. Moreover, the effects of abemaciclib appeared to depend on cyclin D3 expression levels based on the results of the expression analysis of primary aggressive B-cell lymphoma samples. Therefore, abemaciclib has potential as a therapeutic agent for aggressive GC-derived B-cell lymphomas.


Assuntos
Aminopiridinas/farmacologia , Benzimidazóis/farmacologia , Ciclina D3/genética , Linfoma de Células B/genética , Inibidores de Proteínas Quinases/farmacologia , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular , Ensaios de Seleção de Medicamentos Antitumorais , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Linfoma de Células B/tratamento farmacológico , Mutação , Piperazinas/farmacologia , Piridinas/farmacologia
11.
J Vis Exp ; (151)2019 09 20.
Artigo em Inglês | MEDLINE | ID: mdl-31589203

RESUMO

Massage is generally recognized to be beneficial for relieving pain and inflammation. Although previous studies have reported anti-inflammatory effects of massage on skeletal muscles, the molecular mechanisms behind are poorly understood. We have recently developed a simple device to apply local cyclical compression (LCC), which can generate intramuscular pressure waves with varying amplitudes. Using this device, we have demonstrated that LCC modulates inflammatory responses of macrophages in situ and alleviates immobilization-induced muscle atrophy. Here, we describe protocols for the optimization and application of LCC as a massage-like intervention against immobilization-induced inflammation and atrophy of skeletal muscles of mouse hindlimbs. The protocol that we have developed can be useful for investigating the mechanism underlying beneficial effects of physical exercise and massage. Our experimental system provides a prototype of the analytical approach to elucidate the mechanical regulation of muscle homeostasis, although further development needs to be made for more comprehensive studies.


Assuntos
Massagem , Músculo Esquelético , Atrofia Muscular/terapia , Animais , Membro Posterior , Imobilização , Inflamação/terapia , Macrófagos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Músculo Esquelético/fisiologia , Atrofia Muscular/etiologia , Condicionamento Físico Animal , Pressão
12.
Clin Sci (Lond) ; 132(19): 2147-2161, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30209036

RESUMO

Physical inactivity gives rise to numerous diseases and organismal dysfunctions, particularly those related to aging. Musculoskeletal disorders including muscle atrophy, which can result from a sedentary lifestyle, aggravate locomotive malfunction and evoke a vicious circle leading to severe functional disruptions of vital organs such as the brain and cardiovascular system. Although the significance of physical activity is evident, molecular mechanisms behind its beneficial effects are poorly understood. Here, we show that massage-like mechanical interventions modulate immobilization-induced pro-inflammatory responses of macrophages in situ and alleviate muscle atrophy. Local cyclical compression (LCC) on mouse calves, which generates intramuscular pressure waves with amplitude of 50 mmHg, partially restores the myofiber thickness and contracting forces of calf muscles that are decreased by hindlimb immobilization. LCC tempers the increase in the number of cells expressing pro-inflammatory proteins, tumor necrosis factor-α and monocyte chemoattractant protein-1 (MCP-1), including macrophages in situ The reversing effect of LCC on immobilization-induced thinning of myofibers is almost completely nullified when macrophages recruited from circulating blood are depleted by administration of clodronate liposomes. Furthermore, application of pulsatile fluid shear stress, but not hydrostatic pressure, reduces the expression of MCP-1 in macrophages in vitro Together with the LCC-induced movement of intramuscular interstitial fluid detected by µCT analysis, these results suggest that mechanical modulation of macrophage function is involved in physical inactivity-induced muscle atrophy and inflammation. Our findings uncover the implication of mechanosensory function of macrophages in disuse muscle atrophy, thereby opening a new path to develop a novel therapeutic strategy utilizing mechanical interventions.


Assuntos
Macrófagos/fisiologia , Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/fisiopatologia , Atrofia Muscular/fisiopatologia , Estresse Mecânico , Animais , Quimiocina CCL2/metabolismo , Feminino , Elevação dos Membros Posteriores/fisiologia , Macrófagos/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
13.
Curr Protoc Pharmacol ; 71: 12.14.1-12.14.26, 2015 Dec 08.
Artigo em Inglês | MEDLINE | ID: mdl-26646194

RESUMO

Facilitative glucose uptake transport systems are ubiquitous in animal cells and are responsible for transporting glucose across cell surface membranes. Evaluation of glucose uptake is crucial in the study of numerous diseases and metabolic disorders such as myocardial ischemia, diabetes mellitus, and cancer. Detailed in this unit are laboratory methods for assessing glucose uptake into mammalian cells. The unit is divided into five sections: (1) a brief overview of glucose uptake assays in cultured cells; (2) a method for measuring glucose uptake using radiolabeled 3-O-methylglucose; (3) a method for measuring glucose uptake using radiolabeled 2-deoxyglucose (2DG); (4) a microplate method for measuring 2DG-uptake using an enzymatic, fluorometric assay; and (5) a microplate-based method using a fluorescent analog of 2DG.


Assuntos
Transporte Biológico/fisiologia , Fluorometria/métodos , Glucose/metabolismo , 3-O-Metilglucose/metabolismo , Animais , Células Cultivadas , Desoxiglucose/metabolismo , Corantes Fluorescentes/metabolismo , Humanos
14.
Mol Cell Endocrinol ; 393(1-2): 99-108, 2014 Aug 05.
Artigo em Inglês | MEDLINE | ID: mdl-24953974

RESUMO

The present study demonstrates that glabridin, a prenylated isoflavone in licorice, stimulates glucose uptake through the adenosine monophosphate-activated protein kinase (AMPK) pathway in L6 myotubes. Treatment with glabridin for 4h induced glucose uptake in a dose-dependent manner accompanied by the translocation of glucose transporter type 4 (GLUT4) to the plasma membrane. Glabridin needed at least 4h to increase glucose uptake, while it significantly decreased glycogen and increased lactic acid within 15 min. Pharmacological inhibition of AMPK by Compound C suppressed the glabridin-induced glucose uptake, whereas phosphoinositide 3-kinase and Akt inhibition by LY294002 and Akt1/2 inhibitor, respectively, did not. Furthermore, glabridin induced AMPK phosphorylation, and siRNA for AMPK completely abolished glabridin-induced glucose uptake. We confirmed that glabridin-rich licorice extract prevent glucose intolerance accompanied by the AMPK-dependent GLUT4 translocation in the plasma membrane of mice skeletal muscle. These results indicate that glabridin may possess a therapeutic effect on metabolic disorders, such as diabetes and hyperglycemia, by modulating glucose metabolism through AMPK in skeletal muscle cells.


Assuntos
Proteínas Quinases Ativadas por AMP/metabolismo , Glucose/metabolismo , Isoflavonas/farmacologia , Células Musculares/efeitos dos fármacos , Células Musculares/metabolismo , Fenóis/farmacologia , Animais , Transporte Biológico/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Masculino , Camundongos , Reação em Cadeia da Polimerase em Tempo Real , Transdução de Sinais/efeitos dos fármacos
15.
J Cell Sci ; 125(Pt 21): 5051-60, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-22946048

RESUMO

TGF-ß1 plays a key role in cancer progression through induction of various biological effects, including cell migration. Extracellular nucleotides, such as ATP, released from cells play a role in signaling through activation of P2 receptors. We show here that exocytosis of ATP followed by activation of P2 receptors play a key role in TGF-ß1-induced actin remodeling associated with cell migration. Treatment with TGF-ß1 facilitated migration of human lung cancer A549 cells, which was blocked by pretreatment with ecto-nucleotidase and P2 receptor antagonists. ATP and P2 agonists facilitated cell migration. TGF-ß1-induced actin remodeling, which contributes to cell migration, was also suppressed by pretreatment with ecto-nucleotidase and P2 receptor antagonists. Knockdown of P2X7 receptor suppressed TGF-ß1-induced migration and actin remodeling. These results indicate the involvement of TGF-ß1-induced ATP release in cell migration, at least in part, through activation of P2X7 receptors. TGF-ß1 caused release of ATP from A549 cells within 10 minutes. Both ATP-enriched vesicles and expression of a vesicular nucleotide transporter (VNUT) SLC17A9, which is responsible for exocytosis of ATP, were found in cytosol of A549 cells. TGF-ß1 failed to induce release of ATP from SLC17A9-knockdown cells. TGF-ß1-induced cell migration and actin remodeling were also decreased in SLC17A9-knockdown cells. These results suggest the importance of exocytosis of ATP in cell migration. We conclude that autocrine signaling through exocytosis of ATP and activation of P2 receptors is required for the amplification of TGF-ß1-induced migration of lung cancer cells.


Assuntos
Trifosfato de Adenosina/metabolismo , Movimento Celular , Exocitose , Receptores Purinérgicos P2X7/metabolismo , Fator de Crescimento Transformador beta1/fisiologia , Citoesqueleto de Actina/metabolismo , Comunicação Autócrina , Linhagem Celular Tumoral , Expressão Gênica , Técnicas de Silenciamento de Genes , Humanos , Neoplasias Pulmonares , Proteínas de Transporte de Nucleotídeos/genética , Proteínas de Transporte de Nucleotídeos/metabolismo , RNA Interferente Pequeno/genética , Receptores Purinérgicos P2/genética , Receptores Purinérgicos P2/metabolismo , Receptores Purinérgicos P2X7/genética , Vesículas Secretórias/metabolismo , Transdução de Sinais
16.
Cereb Cortex ; 22(5): 1203-14, 2012 May.
Artigo em Inglês | MEDLINE | ID: mdl-21810784

RESUMO

ATP is known to be coreleased with glutamate at certain central synapses. However, the nature of its release is controversial. Here, we demonstrate that ATP release from cultured rat hippocampal neurons is sensitive to RNAi-mediated knockdown of the recently identified vesicular nucleotide transporter (VNUT or SLC17A9). In the intact brain, light microscopy showed particularly strong VNUT immunoreactivity in the cerebellar cortex, the olfactory bulb, and the hippocampus. Using immunoelectron microscopy, we found VNUT immunoreactivity colocalized with synaptic vesicles in excitatory and inhibitory terminals in the hippocampal formation. Moreover, VNUT immunolabeling, unlike that of the vesicular glutamate transporter VGLUT1, was enriched in preterminal axons and present in postsynaptic dendritic spines. Immunoisolation of synaptic vesicles indicated presence of VNUT in a subset of VGLUT1-containing vesicles. Thus, we conclude that VNUT mediates transport of ATP into synaptic vesicles of hippocampal neurons, thereby conferring a purinergic phenotype to these cells.


Assuntos
Trifosfato de Adenosina/metabolismo , Neurônios/metabolismo , Proteínas de Transporte Vesicular/metabolismo , Animais , Western Blotting , Células Cultivadas , Imunofluorescência , Hipocampo/metabolismo , Técnicas Imunoenzimáticas , Imuno-Histoquímica , Camundongos , Microscopia Eletrônica de Transmissão , Microscopia Imunoeletrônica , Neurônios/ultraestrutura , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo Real , Vesículas Sinápticas/metabolismo , Vesículas Sinápticas/ultraestrutura , Proteínas de Transporte Vesicular/isolamento & purificação
17.
Curr Protoc Pharmacol ; Chapter 12: Unit 12.14.1-22, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22147347

RESUMO

Facilitative glucose uptake transport systems are ubiquitous in animal cells and responsible for transporting glucose across the cell surface membrane. Evaluation of glucose uptake is crucial in the study of numerous diseases and metabolic disorders, such as myocardial ischemia, diabetes mellitus, and cancer. Methods for assessing glucose uptake into mammalian cells are detailed in this unit. The work is divided into four sections: (1) a brief overview of glucose uptake assays in cultured cells; (2) a method for measuring glucose uptake using radiolabeled 3-O-methylglucose; (3) a method for measuring glucose uptake using radiolabeled 2-deoxyglucose (2DG); and (4) an improved method for measuring 2DG-uptake using an enzymatic, fluorometric assay, eliminating the need for radiolabeled glucose analogs.


Assuntos
3-O-Metilglucose/farmacocinética , Adipócitos/metabolismo , Proteínas Facilitadoras de Transporte de Glucose/metabolismo , Células Musculares/metabolismo , 3-O-Metilglucose/análise , Animais , Bioensaio/métodos , Células Cultivadas , Desoxiglucose/análise , Desoxiglucose/farmacocinética , Difusão Facilitada/fisiologia , Homeostase/fisiologia , Humanos , Camundongos , Músculo Esquelético/metabolismo , Ensaio Radioligante/métodos , Ratos
18.
J Biol Chem ; 286(50): 42881-7, 2011 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-22052906

RESUMO

The vesicular nucleotide transporter (VNUT) is a secretory vesicle protein that is responsible for the vesicular storage and subsequent exocytosis of ATP (Sawada, K., Echigo, N., Juge, N., Miyaji, T., Otsuka, M., Omote, H., and Moriyama, Y. (2008) Proc. Natl. Acad. Sci. U.S.A. 105, 5683-5686). Because VNUT actively transports ATP in a membrane potential (Δψ)-dependent manner irrespective of divalent cations such as Mg(2+) and Ca(2+), VNUT recognizes free ATP as a transport substrate. However, whether or not VNUT transports chelating complexes with divalent cations remains unknown. Here, we show that proteoliposomes containing purified VNUT actively took up Mg(2+) when ATP was present, as detected by atomic absorption spectroscopy. The VNUT-containing proteoliposomes also took up radioactive Ca(2+) upon imposing Δψ (positive-inside) but not ΔpH. The Δψ-driven Ca(2+) uptake required ATP and a millimolar concentration of Cl(-), which was inhibited by Evans blue, a specific inhibitor of SLC17-type transporters. VNUT in which Arg-119 was specifically mutated to alanine, the counterpart of the essential amino acid residue of the SLC17 family, lost the ability to take up both ATP and Ca(2+). Ca(2+) uptake was also inhibited in the presence of various divalent cations such as Mg(2+). Kinetic analysis indicated that Ca(2+) or Mg(2+) did not affect the apparent affinity for ATP. RNAi of the VNUT gene in PC12 cells decreased the vesicular Mg(2+) concentration to 67.7%. These results indicate that VNUT transports both nucleotides and divalent cations probably as chelating complexes and suggest that VNUT functions as a divalent cation importer in secretory vesicles under physiological conditions.


Assuntos
Cátions Bivalentes/metabolismo , Nucleotídeos/metabolismo , Proteínas Vesiculares de Transporte de Neurotransmissores/metabolismo , Trifosfato de Adenosina/metabolismo , Animais , Transporte Biológico , Cálcio/metabolismo , Proteínas de Transporte de Glutamato da Membrana Plasmática/genética , Proteínas de Transporte de Glutamato da Membrana Plasmática/metabolismo , Humanos , Cinética , Magnésio/metabolismo , Camundongos , Células PC12 , Ratos , Proteínas Cotransportadoras de Sódio-Fosfato Tipo III/metabolismo , Proteínas Vesiculares de Transporte de Neurotransmissores/genética
19.
Mol Nutr Food Res ; 55(3): 467-75, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20938990

RESUMO

SCOPE: Glucose uptake in skeletal muscle is crucial for glucose homeostasis. METHODS AND RESULTS: Insulin and muscle contraction increase glucose uptake accompanied by the translocation of glucose transporter (GLUT) 4. In a search for promising foods, which can increase glucose uptake in skeletal muscle, we screened for active polyphenols by assaying for uptake of 2-deoxyglucose (2DG) in rat L6 muscle cells. Among 37 compounds, 4-hydroxyderricin and xanthoangelol, prenylated chalcones abundant in Ashitaba (Angelica keiskei Koidzumi, family Apiaceae), significantly increased 2DG uptake in L6 cells by 1.9-fold at 10 µM, compared with the level in DMSO-treated control cells. Next, we investigated the effect of these chalcones on the translocation of GLUT4 and its underlying mechanisms. The chalcones increased the GLUT4 level in the plasma membrane of L6 cells, but activated neither protein kinase C ζ/λ, Akt, nor adenosine monophosphate-activated protein kinase, all of which regulate the GLUT4 translocation. Interestingly, the oral administration of a titrated chalcone-enriched Ashitaba extract containing 150.6 mg/g (dry base) of 4-hydroxyderricin and 146.0 mg/g (dry base) of xanthoangelol suppressed acute hyperglycemia in oral glucose tolerance tests of mice. CONCLUSIONS: Ashitaba is a promising functional food for the maintenance of the blood glucose level by inducing skeletal muscle-associated glucose uptake.


Assuntos
Chalcona/análogos & derivados , Desoxiglucose/farmacocinética , Transportador de Glucose Tipo 4/metabolismo , Glucose/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Prenilação , Angelica/química , Animais , Linhagem Celular , Chalcona/farmacologia , Flavonoides/análise , Flavonoides/farmacologia , Teste de Tolerância a Glucose , Hiperglicemia/dietoterapia , Masculino , Camundongos , Camundongos Endogâmicos ICR , Proteínas Musculares , Músculo Esquelético , Fenóis/análise , Fenóis/farmacologia , Polifenóis , Proteína Quinase C/metabolismo , Transporte Proteico , Distribuição Aleatória , Ratos
20.
Proc Natl Acad Sci U S A ; 106(7): 2447-52, 2009 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-19168636

RESUMO

Alkaloids play a key role in plant defense mechanisms against pathogens and herbivores, but the plants themselves need to cope with their toxicity as well. The major alkaloid of the Nicotiana species, nicotine, is translocated via xylem transport from the root tissues where it is biosynthesized to the accumulation sites, the vacuoles of leaves. To unravel the molecular mechanisms behind this membrane transport, we characterized one transporter, the tobacco (Nicotiana tabacum) jasmonate-inducible alkaloid transporter 1 (Nt-JAT1), whose expression was coregulated with that of nicotine biosynthetic genes in methyl jasmonate-treated tobacco cells. Nt-JAT1, belonging to the family of multidrug and toxic compound extrusion transporters, was expressed in roots, stems, and leaves, and localized in the tonoplast of leaf cells. When produced in yeast cells, Nt-JAT1 occurred mainly in the plasma membrane and showed nicotine efflux activity. Biochemical analysis with proteoliposomes reconstituted with purified Nt-JAT1 and bacterial F(0)F(1)-ATPase revealed that Nt-JAT1 functioned as a proton antiporter and recognized endogenous tobacco alkaloids, such as nicotine and anabasine, and other alkaloids, such as hyoscyamine and berberine, but not flavonoids. These findings strongly suggest that Nt-JAT1 plays an important role in the nicotine translocation by acting as a secondary transporter responsible for unloading of alkaloids in the aerial parts and deposition in the vacuoles.


Assuntos
Antiporters/metabolismo , Nicotiana/metabolismo , Nicotina/metabolismo , Proteínas de Plantas/fisiologia , Antiporters/química , Transporte Biológico , Clonagem Molecular , Análise por Conglomerados , Perfilação da Expressão Gênica , Regulação da Expressão Gênica de Plantas , Ligação Genética , Modelos Biológicos , Dados de Sequência Molecular , Folhas de Planta/metabolismo , Proteínas de Plantas/metabolismo , Proteolipídeos/química , Saccharomyces cerevisiae/metabolismo , Análise de Sequência de DNA
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