Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
PLoS One ; 15(4): e0230933, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32240225

RESUMO

Insomnia is a major comorbid symptom of chronic pain and is likely to affect caregiver burden. This cross-sectional study investigated the association between insomnia in chronic pain patients and family caregiver burden. Participants were 60 patients with chronic pain of ≥3 months duration. Demographic and clinical information were collected using the Athens Insomnia Scale (AIS), the Pain Disability Assessment Scale (PDAS), the Hospital Anxiety and Depression Scale (HADS), and a pain intensity numerical rating scale (NRS). Family members who accompanied chronic pain patients to hospital completed the Zarit Burden Interview (ZBI). Univariate regression analysis and multiple regression analysis were conducted to clarify the associations between ZBI scores and total/subscale AIS scores. Covariates were age; sex; pain duration; and scores on the PDAS, HADS anxiety subscale, HADS depression subscale, and NRS. Insomnia was independently associated with ZBI scores [ß: 0.27, 95% confidence interval (CI): 0.07-0.52, p = 0.001]. Scores on the AIS subscale of physical and mental functioning during the day were significantly associated with ZBI scores (ß: 0.32, 95% CI: 0.05-0.59, p = 0.007). In conclusion, the findings suggest that in chronic pain patients, comorbid insomnia and physical and mental daytime functioning is associated with family caregiver burden independently of pain duration, pain-related disability, and pain intensity.


Assuntos
Cuidadores/psicologia , Cuidadores/estatística & dados numéricos , Dor Crônica/fisiopatologia , Dor Crônica/psicologia , Distúrbios do Início e da Manutenção do Sono/fisiopatologia , Distúrbios do Início e da Manutenção do Sono/psicologia , Adaptação Psicológica/fisiologia , Idoso , Ansiedade/psicologia , Efeitos Psicossociais da Doença , Estudos Transversais , Depressão/psicologia , Avaliação da Deficiência , Pessoas com Deficiência/psicologia , Família/psicologia , Feminino , Humanos , Masculino , Medição da Dor/estatística & dados numéricos , Qualidade de Vida/psicologia , Inquéritos e Questionários
2.
PLoS One ; 14(4): e0215404, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30990842

RESUMO

PURPOSE: This study aimed to investigate whether changes in psychosocial factors and pain severity were associated with reduction in disability due to pain among patients with chronic pain. We hypothesized that increased self-efficacy would reduce disability. PATIENTS AND METHODS: This longitudinal observational study included 72 patients. Patients' psychological and physical variables were assessed before and after 3 months of treatment. Demographic and clinical information were collected, including the Pain Disability Assessment Scale (PDAS), the Pain Self-Efficacy Questionnaire (PSEQ), the Hospital Depression and Anxiety Scale, and the Numeric Rating Scale (NRS) to assess pain intensity. First, univariate regression analyses were conducted to clarify associations between change in PDAS and sex, age, pain duration, changes in psychosocial factors (self-efficacy, anxiety, and depression) and change in pain intensity. Second, multivariate regression was conducted using the variables identified in the univariate analyses (PSEQ and NRS) to detect the most relevant factor for reducing disability. RESULTS: Univariate regression analyses clarified that changes in PSEQ (ß = -0.31; 95% CI: -0.54--0.08, p = 0.008) and NRS (ß = 0.24; 95% confidence interval [CI]: 0.01-0.47, p = 0.04) were associated with reduction in PDAS. Multivariate regression analysis demonstrated that change in PSEQ (ß = 0.26; 95% CI: -0.50--0.02; p = 0.01) was associated with a reduction in disability, independent of change in NRS. CONCLUSION: These findings suggest improved self-efficacy is associated with reduced disability in patients with chronic pain, independent of reduction in pain intensity. Focusing on improvement in self-efficacy may be an effective strategy in chronic pain treatment in addition to pain relief.


Assuntos
Ansiedade , Dor Crônica , Depressão , Avaliação da Deficiência , Pessoas com Deficiência , Autoeficácia , Inquéritos e Questionários , Adulto , Ansiedade/fisiopatologia , Ansiedade/psicologia , Dor Crônica/fisiopatologia , Dor Crônica/psicologia , Depressão/fisiopatologia , Depressão/psicologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Medição da Dor
3.
Sci Rep ; 8(1): 3005, 2018 02 14.
Artigo em Inglês | MEDLINE | ID: mdl-29445227

RESUMO

The proto-oncogene c-Myc encodes a short-lived protein c-Myc that regulates various cellular processes including cell growth, differentiation and apoptosis. Degradation of c-Myc is catalyzed by the proteasome and requires phosphorylation of Thr-58 for ubiquitination by E3 ubiquitin ligase, Fbxw7/ FBW7. Here we show that a polyamine regulatory protein, antizyme 2 (AZ2), interacts with c-Myc in the nucleus and nucleolus, to accelerate proteasome-mediated c-Myc degradation without ubiquitination or Thr-58 phosphorylation. Polyamines, the inducer of AZ2, also destabilize c-Myc in an AZ2-dependent manner. Knockdown of AZ2 by small interfering RNA (siRNA) increases nucleolar c-Myc and also cellular pre-rRNA whose synthesis is promoted by c-Myc. AZ2-dependent c-Myc degradation likely operates under specific conditions such as glucose deprivation or hypoxia. These findings reveal the targeting mechanism for nucleolar ubiquitin-independent c-Myc degradation.


Assuntos
Núcleo Celular/metabolismo , Hipóxia/metabolismo , Proteínas/metabolismo , Proteínas Proto-Oncogênicas c-myc/metabolismo , Nucléolo Celular/metabolismo , Células HEK293 , Humanos , Fosforilação , Proteínas/genética , Proteólise , Proto-Oncogene Mas , RNA Interferente Pequeno/genética , Ubiquitina/metabolismo , Ubiquitinação
4.
Histochem Cell Biol ; 149(2): 161-167, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29159700

RESUMO

No expression and distribution patterns of polyamines (PAs), spermine, spermidine, and their precursor putrescine in mammalian hair follicle are available, although polyamines are known to correlate well with hair growth and epidermal tumor genesis. Immunohistochemistry (IHC) using our original two monoclonal antibodies (mAbs) ASPM-29 specific for spermine or spermidine, and APUT-32 specific for putrescine allowed us to detect immunoreactivity for polyamines in hair follicles from normal adult rats. A wide range of immunoreactivity for the total spermine and spermidine was observed in the compartments of hair follicle: The highest degree of immunoreactivity for polyamines was observed in the matrix, in the Huxley's layer, in the deeper Henle's layer, and in the cuticle of the inner root sheath/the hair cuticle, while moderate immunoreactivity existed in the lower-to-mid cortex and the companion layer, followed by lower immunoreactivity in the outer root sheath, including the bulge region and in the deeper medulla, in which the immunoreactivity was also evident in their nuclei. In addition, somewhat surprisingly, with IHC by APUT-32 mAb, we detected significant levels of putrescine in the compartments, in which the immunostaining pattern was the closely similar to that of the total spermine and spermidine. Thus, among these compartments, the cell types of the matrix, the Huxley's layer, the deeper Henle's layer, and the cuticle of the inner root sheath/the hair cuticle seem to have the biologically higher potential in compartments of anagen hair follicle, maybe suggesting that they are involved more critically in the biological event of hair growth. In addition, we noted sharp differences of immunostaining by IHCs between ASPM-29 mAb and APUT-32 mAb in the epidermis cells and fibroblast. ASPM-29 mAb resulted in strong staining in both the cell types, but APUT-32 mAb showed only very light staining in both types. Consequently, the use of the two IHCs could be extremely useful in further studies on hair cycle and epidermal tumor genesis experimentally or clinically.


Assuntos
Folículo Piloso/química , Putrescina/biossíntese , Espermidina/biossíntese , Espermina/biossíntese , Animais , Anticorpos Monoclonais/imunologia , Folículo Piloso/citologia , Folículo Piloso/imunologia , Putrescina/análise , Putrescina/imunologia , Ratos , Espermidina/análise , Espermidina/imunologia , Espermina/análise , Espermina/imunologia
5.
Biochem Biophys Res Commun ; 471(4): 646-51, 2016 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-26915799

RESUMO

Antizyme (AZ) regulates cellular polyamines (i.e., putrescine, spermidine, and spermine) through binding to ornithine decarboxylase and subsequent ubiquitin-independent degradation of the enzyme protein by the 26S proteasome. Screening for AZ-binding proteins using a yeast two-hybrid system identified ATP citrate lyase (ACLY), a cytosolic enzyme which catalyzes the production of acetyl-CoA that is used for lipid anabolism or acetylation of cellular components. We confirmed that both AZ1 and AZ2 bind to ACLY and AZ colocalizes with ACLY to the cytoplasm. Unexpectedly, neither AZ1 nor AZ2 accelerated ACLY degradation. Additionally, purified AZ, particularly AZ1, increased the activity of purified ACLY in a dose-dependent manner in vitro, suggesting that AZ activates ACLY through protein-protein interaction. Polyamines themselves had no effect on the ACLY activity in vitro. Knockdown of AZ1 and/or AZ2 in human cancer cells significantly decreased the ACLY activity as well as cellular levels of acetyl-CoA and cholesterol. Our results are the first to show the crosstalk between polyamine and acetyl-CoA metabolism. We hypothesize that AZ may promote acetyl-CoA synthesis to downregulate spermidine and spermine through acetylation.


Assuntos
ATP Citrato (pro-S)-Liase/metabolismo , Acetilcoenzima A/biossíntese , Neoplasias/enzimologia , Proteínas/metabolismo , Espermidina/metabolismo , Acetilação , Proteínas de Transporte , Técnicas de Silenciamento de Genes , Humanos , Lipogênese , Complexo de Endopeptidases do Proteassoma/metabolismo , Proteínas/genética , Proteólise , Técnicas do Sistema de Duplo-Híbrido
6.
BMC Cancer ; 14: 799, 2014 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-25366985

RESUMO

BACKGROUND: Epithelial ovarian cancer (EOC) is the most common cause of gynecological malignancy-related mortality. Ovarian clear cell carcinoma (CCC) has unique clinical characteristics and behaviors that differ from other histological types of EOC, including a frequent association with endometriosis and a highly chemoresistant nature, resulting in poor prognosis. However, factors underlying its malignant behavior are still poorly understood. Aberrant expression of microRNAs has been shown to be involved in oncogenesis, and microRNA-21 (miR-21) is frequently overexpressed in many types of cancers. The aim of this study was to investigate the role of miR-21 in 17q23-25 amplification associated with CCC oncogenesis. METHODS: We identified 17q23-25 copy number aberrations among 28 primary CCC tumors by using a comparative genomic hybridization method. Next, we measured expression levels of the candidate target genes, miR-21 and PPM1D, for 17q23-25 amplification by real-time RT-PCR analysis and compared those data with copy number status and clinicopathological features. In addition, immunohistochemical analysis of PTEN (a potential target of miR-21) was performed using the same primary CCC cases. We investigated the biological significance of miR-21 overexpression in CCC using a loss-of-function antisense approach. RESULTS: 17q23-25 amplification with both miR-21 overexpression and PTEN protein loss was detected in 4/28 CCC cases (14.2%). The patients with 17q23-25 amplification had significantly shorter progression-free and overall survival than those without 17q23-25 amplification (log-rank test: p = 0.0496; p = 0.0469, respectively). A significant correlation was observed between miR-21 overexpression and endometriosis. Both PTEN mRNA and PTEN protein expression were increased by miR-21 knockdown in CCC cells. We also confirmed that miR-21 directly bound to the 3'-untranslated region of PTEN mRNA using a dual-luciferase reporter assay. CONCLUSIONS: MiR-21 is a possible driver gene other than PPM1D for 17q23-25 amplification in CCC. Aberrant expression of miR-21 by chromosomal amplification might play an important role in CCC carcinogenesis through the regulation of the PTEN tumor suppressor gene.


Assuntos
Adenocarcinoma de Células Claras/genética , Cromossomos Humanos Par 17/genética , Amplificação de Genes , MicroRNAs/genética , Neoplasias Ovarianas/genética , Adenocarcinoma de Células Claras/mortalidade , Adenocarcinoma de Células Claras/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Hibridização Genômica Comparativa , Feminino , Seguimentos , Dosagem de Genes , Expressão Gênica , Regulação Neoplásica da Expressão Gênica , Humanos , Pessoa de Meia-Idade , Metástase Neoplásica , Estadiamento de Neoplasias , Neoplasias Ovarianas/patologia , PTEN Fosfo-Hidrolase/genética , PTEN Fosfo-Hidrolase/metabolismo , Prognóstico
7.
Amino Acids ; 46(3): 575-83, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24077669

RESUMO

Antizyme inhibitor 1 (Azin1), a positive regulator of cellular polyamines, is induced by various proliferative stimuli and repressed by polyamines. It has been reported that the translational repression of Azin1 by polyamines involves an upstream open reading frame on the mRNA, but little has been known about polyamine effect on its transcription or splicing. We found multiple forms of Azin1 transcripts formed by alternative splicing and initiation of transcription from putative alternative start sites. One of the novel splice variants, Azin1-X, has a premature termination codon on 5' extension of exon 7, encodes a C-terminal truncated form of protein (Azin1ΔC), and is subject to nonsense-mediated mRNA decay. 2-Difluoromethylornithine (DFMO), an inhibitor of polyamine synthesis, increased both transcription from the canonical transcription start site and the ratio of the full-length mRNA to Azin1-X mRNA, whereas polyamines show the opposite effect. Thus, polyamines regulate two novel steps of Azin1 expression, namely the transcription and a particular splicing pattern, both of which may affect the level of mRNA encoding the full-length active Azin1 protein.


Assuntos
Proteínas de Transporte/metabolismo , Poliaminas/metabolismo , RNA Mensageiro/metabolismo , Animais , Proteínas de Transporte/genética , Células Cultivadas , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL , RNA Mensageiro/genética
8.
Methods Mol Biol ; 720: 237-67, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21318878

RESUMO

Antizyme (AZ) is a key molecule in feedback regulation of cellular polyamines. It is induced by polyamines through stimulation of ribosomal frameshifting during its translation. In mammals, AZ is diverged into three paralogs, AZ1-3. Tissue and subcellular distribution are different among the paralogs, as determined by immunochemical methods or expression of fluorescent-tagged proteins. Only AZ2 is known to be phosphorylated. AZ regulates cellular polyamine levels through multiple mechanisms. It binds to ornithine decarboxylase (ODC) to form an inactive complex and to trigger degradation of ODC by 26S proteasomes. The AZ activity to promote ODC degradation can be measured both in vitro and in cells. AZ also inhibits cellular uptake of polyamines. This chapter comprises seven subchapters describing methods for studying expression and function of AZ.


Assuntos
Ensaios Enzimáticos/métodos , Proteínas/metabolismo , Animais , Transporte Biológico/efeitos dos fármacos , Western Blotting , Extratos Celulares , Linhagem Celular Tumoral , Inibidores Enzimáticos/farmacologia , Mudança da Fase de Leitura do Gene Ribossômico/efeitos dos fármacos , Humanos , Imuno-Histoquímica , Espaço Intracelular/efeitos dos fármacos , Espaço Intracelular/metabolismo , Rim/enzimologia , Camundongos , Fosforilação/efeitos dos fármacos , Poliaminas/metabolismo , Processamento de Proteína Pós-Traducional/efeitos dos fármacos , Proteínas/antagonistas & inibidores , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Transfecção
9.
J Nutr Sci Vitaminol (Tokyo) ; 56(5): 271-8, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-21228496

RESUMO

Cytokeratin (CK) 18 M30 antigen has been proposed as a diagnostic marker of nonalcoholic fatty liver disease (NAFLD). We studied serum CK18 M30 antigen level and examined the correlations among CK18 and biological data, dietary intake, and plasma fatty acid composition in middle-aged Japanese males with (NAFLD; n=42) and without NAFLD (control; n=35). NAFLD was diagnosed if subjects showed fatty liver on abdominal ultrasonography and their alcohol consumption was <20 g/d. They were also confirmed to have negative serological results for tests of autoimmune liver disease and hepatitis B and C. In the NAFLD group, body mass index, waist circumference, serum M30 antigen, alanine transaminase (ALT), cholinesterase, triacylglycerol, LDL-cholesterol, and HbA1c were significantly higher than in the control group. In the fatty acid analysis of plasma phospholipids, significantly higher dihomo-γ-linolenic acid (DGLA), total saturated fatty acids (SFA), and palmitic/linoleic acid ratio as well as lower arachidonic acid/DGLA ratio were observed in the NAFLD group compared with the control group. In the NAFLD group, M30 antigen was correlated positively with serum ALT, plasma DGLA, dietary SFA, and serum TNF-α as determined by partial correlation analysis controlled for BMI. On the basis of multivariate regression analysis using a stepwise method, M30 antigen was significantly associated with ALT and plasma DGLA. Regarding the determinants of NAFLD as revealed by logistic regression analysis, a high odds ratio was observed for plasma DGLA. In conclusion, members of the NAFLD group showed higher levels of serum CK18 M30 antigen and M30 antigen was strongly associated with serum ALT and plasma DGLA. Abnormal fatty acid metabolism may be a factor that causes aggravation of NAFLD.


Assuntos
Dieta , Ingestão de Alimentos , Queratina-18/sangue , Ácido 8,11,14-Eicosatrienoico , Adulto , Alanina Transaminase/sangue , Povo Asiático , Índice de Massa Corporal , Ácidos Graxos/sangue , Fígado Gorduroso/sangue , Fígado Gorduroso/epidemiologia , Humanos , Japão/epidemiologia , Masculino , Pessoa de Meia-Idade , Análise Multivariada , Hepatopatia Gordurosa não Alcoólica , Análise de Regressão , Fator de Necrose Tumoral alfa/sangue , Circunferência da Cintura
10.
J Cell Biochem ; 108(4): 1012-21, 2009 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-19725046

RESUMO

Antizymes (AZs) are polyamine-induced proteins that negatively regulate cellular polyamine synthesis and uptake. Three antizyme isoforms are conserved among mammals. AZ1 and AZ2 have a broad tissue distribution, while AZ3 is testis specific. Both AZ1 and AZ2 inhibit ornithine decarboxylase (ODC) activity by binding to ODC monomer and target it to the 26S proteasome at least in vivo. Both also inhibit extra-cellular polyamine uptake. Despite their being indistinguishable by these criteria, we show here using enhanced green fluorescent protein (EGFP)-AZ2 fusion protein that in mammalian cells, the subcellular location of AZ2 is mainly in the nucleus, and is different from that of AZ1. The C-terminal part of AZ2 is necessary for the nuclear distribution. Within a few hours, a shift in the distribution of EGFP-AZ2 fusion protein from cytoplasm to the nucleus or from nucleus to cytoplasm is observable in NIH3T3 cells. In addition, we found that in cells a majority of AZ2, but not AZ1, is phosphorylated at Ser-186, likely by protein kinase CK2. There may be a specific function of AZ2 in the nucleus.


Assuntos
Poliaminas/química , Complexo de Endopeptidases do Proteassoma/química , Proteínas/metabolismo , Sequência de Aminoácidos , Animais , Células COS , Núcleo Celular/metabolismo , Chlorocebus aethiops , Citoplasma/metabolismo , Proteínas de Fluorescência Verde/metabolismo , Camundongos , Dados de Sequência Molecular , Células NIH 3T3 , Fosforilação , Isoformas de Proteínas , Proteínas/química , Homologia de Sequência de Aminoácidos
11.
Drug Deliv ; 16(3): 153-9, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19514975

RESUMO

To achieve the effective intracellular delivery of siRNA and silence specific genes, various types of conjugates between cell-penetrating peptides (CPPs; Transportan, Penetratin, Tat) and cationic peptides were developed. Uptake, intracellular localization, cytotoxicity, and biological activity of siRNA were significantly dependent on the kind of CPP used and the length of the cationic peptides in the conjugate. Transportan-based conjugates yielded both high internalization of siRNA and strong gene silencing activity, while Penetratin- and Tat-based conjugates did not. These different properties of CPPs emphasize the importance of careful peptide selection and design when attempting the application of CPP technology.


Assuntos
Proteínas de Transporte/química , Oligopeptídeos/química , Peptídeos/química , RNA Interferente Pequeno/administração & dosagem , Permeabilidade da Membrana Celular/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Peptídeos Penetradores de Células , Sistemas de Liberação de Medicamentos , Galanina/química , Inativação Gênica , Células HeLa , Humanos , Luciferases/antagonistas & inibidores , Luciferases/genética , Microscopia de Fluorescência , Oligopeptídeos/síntese química , Transporte Proteico/efeitos dos fármacos , Proteínas Recombinantes de Fusão/química , Células Tumorais Cultivadas , Venenos de Vespas/química
12.
Exp Cell Res ; 315(13): 2301-11, 2009 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-19426728

RESUMO

Antizyme inhibitor (AIn), a homolog of ODC, binds to antizyme and inactivates it. We report here that AIn increased at the G1 phase of the cell cycle, preceding the peak of ODC activity in HTC cells in culture. During interphase AIn was present mainly in the cytoplasm and turned over rapidly with the half-life of 10 to 20 min, while antizyme was localized in the nucleus. The level of AIn increased again at the G2/M phase along with ODC, and the rate of turn-over of AIn in mitotic cells decreased with the half-life of approximately 40 min. AIn was colocalized with antizyme at centrosomes during the period from prophase through late anaphase and at the midzone/midbody during telophase. Thereafter, AIn and antizyme were separated and present at different regions on the midbody at late telophase. AIn disappeared at late cytokinesis, whereas antizyme remained at the cytokinesis remnant. Reduction of AIn by RNA interference caused the increase in the number of binucleated cells in HTC cells in culture. These findings suggested that AIn contributed to a rapid increase in ODC at the G1 phase and also played a role in facilitating cells to complete mitosis during the cell cycle.


Assuntos
Proteínas de Transporte/metabolismo , Ciclo Celular/fisiologia , Ornitina Descarboxilase/metabolismo , Animais , Antineoplásicos/farmacologia , Proteínas de Transporte/genética , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sistema Livre de Células , Eflornitina/metabolismo , Estabilidade Enzimática , Nocodazol/farmacologia , Inibidores da Ornitina Descarboxilase , Poliaminas/metabolismo , Proteínas/metabolismo , RNA Mensageiro/metabolismo , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos
13.
Endocr Relat Cancer ; 16(2): 649-59, 2009 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-19349429

RESUMO

Human pancreatic tumor cell lines - AsPC-1, PANC-1, MIA paca2, KP-1 and KP-59 cells - can be induced to differentiate into pancreatic hormone-producing cells by brief trypsin treatment and subsequent culture in a serum-free, chemically defined medium. During culture, AsPC-1 cells formed cell clusters resembling the pancreatic islets, expressed genes associated with the pancreatic development and produced glucagon but not insulin. When PANC-1, MIA paca2, KP-1 and KP-59 cells were treated and cultured the same way, they underwent similar morphological changes and produced insulin and glucagon. We used these systems to identify intracellular regulatory molecules involved in the conversion of pancreatic tumor cells into glucagon-producing cells. We found that the expression of antizyme 1 (AZ1), a negative regulator of ornithine decarboxylase, was increased and its localization was altered from the nucleus to the cytoplasm during AsPC-1 cell differentiation. Transient transfection of AsPC-1 cells with AZ1 siRNA resulted in inhibition of the morphological and functional cell differentiation as well as the specific suppression of AZ1 expression. By contrast, constitutive overexpression of AZ1 in AsPC-1 cells led to the enhancement of glucagon production. We also found that PANC-1 cells reduced the expression of glucagon mRNA when treated with AZ1 siRNA. These results suggested that AZ1 was necessary for the conversion of pancreatic tumor cells into glucagon-producing cells. Glucagon production in AsPC-1 cells was not affected by addition of putrescine, suggesting that the polyamines were not directly involved in the AZ1-mediated conversion of pancreatic tumor cells to differentiated state.


Assuntos
Adenocarcinoma/metabolismo , Diferenciação Celular , Inibidores Enzimáticos/farmacologia , Glucagon/biossíntese , Neoplasias Pancreáticas/metabolismo , Proteínas/metabolismo , Adenocarcinoma/patologia , Animais , Núcleo Celular/metabolismo , Citoplasma/metabolismo , Humanos , Neoplasias Pancreáticas/patologia , Poliaminas/metabolismo , Proteínas/antagonistas & inibidores , Proteínas/genética , RNA Interferente Pequeno/farmacologia , Ratos , Células Tumorais Cultivadas
14.
J Biol Chem ; 284(12): 8174-84, 2009 Mar 20.
Artigo em Inglês | MEDLINE | ID: mdl-19158080

RESUMO

Pneumocystis pneumonia (PcP) is the most common opportunistic disease in immunocompromised patients. Alveolar macrophages are responsible for the clearance of Pneumocystis organisms; however, they undergo a high rate of apoptosis during PcP due to increased intracellular polyamine levels. In this study, the sources of polyamines and mechanisms of polyamine increase and polyamine-induced apoptosis were investigated. The level of ornithine decarboxylase (ODC) was elevated in alveolar macrophages, and the number of alveolar macrophages that took up exogenous polyamines was increased 20-fold during PcP. Monocytes, B lymphocytes, and CD8+ T lymphocytes that were recruited into the lung during PcP expressed high levels of ornithine decarboxylase, suggesting that these cells are sources of polyamines. Both protein and mRNA levels of antizyme inhibitor (AZI) were increased in alveolar macrophages during PcP. This AZI overexpression correlated with increased polyamine uptake by alveolar macrophages, because AZI expression knockdown decreased the polyamine uptake ability of these cells. AZI expression knockdown also decreased the apoptosis rate of alveolar macrophages. Pneumocystis organisms and zymosan A were found to induce AZI overexpression in alveolar macrophages, suggesting that beta-glucan, which is the major component of the Pneumocystis cell wall, induces AZI overexpression. The levels of mRNA, protein, and activity of polyamine oxidase were increased in alveolar macrophages during PcP, indicating that the H(2)O(2) generated during polyamine catabolism caused alveolar macrophages to undergo apoptosis. Taken together, results of this study indicate that Pneumocystis organisms induce AZI overexpression in alveolar macrophages, leading to increased polyamine synthesis and uptake and apoptosis rate of these cells.


Assuntos
Apoptose , Proteínas de Transporte/biossíntese , Regulação da Expressão Gênica , Macrófagos Alveolares/metabolismo , Pneumocystis carinii , Pneumonia por Pneumocystis/metabolismo , Poliaminas/metabolismo , Animais , Linfócitos B/imunologia , Linfócitos B/metabolismo , Linfócitos T CD8-Positivos/imunologia , Linfócitos T CD8-Positivos/metabolismo , Proteínas de Transporte/imunologia , Parede Celular/imunologia , Parede Celular/metabolismo , Humanos , Peróxido de Hidrogênio/imunologia , Peróxido de Hidrogênio/metabolismo , Macrófagos Alveolares/imunologia , Macrófagos Alveolares/fisiologia , Masculino , Ornitina Descarboxilase/imunologia , Ornitina Descarboxilase/metabolismo , Inibidores da Ornitina Descarboxilase , Pneumonia por Pneumocystis/imunologia , Pneumonia por Pneumocystis/patologia , Poliaminas/imunologia , Ratos , Ratos Sprague-Dawley , beta-Glucanas/imunologia , beta-Glucanas/metabolismo
15.
Genes Cells ; 14(1): 79-87, 2009 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-19077035

RESUMO

Ornithine decarboxylase (ODC) antizyme inhibitor (AZI) has been shown to regulate ODC activity in cell cultures. However, its biological functions in an organism remain unknown. An embryonic stem (ES) cell clone was established, in which the Azin1 gene was disrupted by the gene trap technique. To identify the function of Azin1 gene in vivo, a mutant mouse line was generated using these trapped ES cells. Homozygous mutant mice died at P0 with abnormal liver morphology. Further analysis indicated that the deletion of Azin1 in homozygous mice resulted in the degradation of ODC, and reduced the biosynthesis of putrescine and spermidine. Our results thus show that AZI plays an important role in regulating the levels of ODC, putrescine and spermidine in mice, and is essential for the survival of mice.


Assuntos
Proteínas de Transporte/metabolismo , Animais , Proteínas de Transporte/genética , Linhagem Celular , Feminino , Regulação da Expressão Gênica no Desenvolvimento , Vetores Genéticos/genética , Heterozigoto , Homozigoto , Masculino , Camundongos , Camundongos Mutantes , Fenótipo , Poliaminas/metabolismo
16.
Lipids ; 43(4): 325-33, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18320252

RESUMO

Eicosapentaenoic acid (EPA) (1.8 g/day) was administered to 12 chronic hepatitis C patients receiving combination therapy of pegylated interferon (PEG-IFN) alpha-2b and ribavirin for 48 weeks (EPA group). Twelve patients were not administered EPA (control group). All patients also received vitamin E and C (300, 600 mg/day, respectively) during the therapy. Serum alanine aminotransferase improved to a normal level in 8 of 12 patients from the EPA group and 6 of 12 patients from the control group after 12 weeks. Lymphocyte counts decreased significantly after 8 weeks in the control group, but not the EPA group. T-helper (Th) 1 decreased after 4 weeks in the control group, but not in the EPA group (two-way ANOVA; P < 0.05). Th1/Th2 ratios were elevated in 9 of 12 patients in the EPA group, and 3 out of 12 in the control group (P < 0.05) after 8 weeks. After 12 weeks, the arachidonic acid/EPA molar ratio of erythrocyte membrane phospholipid correlated negatively with the leukocyte count (n = 24, r = -0.439, P < 0.05) and the neutrophil count (n = 24, r = -0.671, P < 0.02). The hemoglobin level improved after 48 weeks compared with 24 weeks in only the EPA group. These findings suggest that EPA supplementation may be useful in therapy for chronic hepatitis C.


Assuntos
Antivirais/administração & dosagem , Ácido Eicosapentaenoico/administração & dosagem , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/administração & dosagem , Ribavirina/administração & dosagem , Alanina Transaminase/sangue , Antivirais/uso terapêutico , Ácido Ascórbico/administração & dosagem , Suplementos Nutricionais , Quimioterapia Combinada , Ácido Eicosapentaenoico/uso terapêutico , Feminino , Humanos , Interferon alfa-2 , Interferon-alfa/uso terapêutico , Masculino , Pessoa de Meia-Idade , Polietilenoglicóis , Proteínas Recombinantes , Ribavirina/uso terapêutico , Vitamina E/administração & dosagem
17.
Biol Pharm Bull ; 30(10): 1943-6, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17917267

RESUMO

A sensitive method for the determination of polyamines in mammalian cells was described using electrospray ionization and time-of-flight mass spectrometer. This method was 50-fold more sensitive than the previous method using ionspray ionization and quadrupole mass spectrometer. The method employed the partial purification and derivatization of polyamines, but allowed a measurement of multiple samples which contained picomol amounts of polyamines. Time required for data acquisition of one sample was approximately 2 min. The method was successfully applied for the determination of reduced spermidine and spermine contents in cultured cells under the inhibition of aminopropyltransferases. In addition, a new proper internal standard was proposed for the tracer experiment using (15)N-labeled polyamines.


Assuntos
Espermidina/análise , Espermina/análise , Linhagem Celular , Células/química , Cromatografia Líquida de Alta Pressão , Cicloexilaminas/farmacologia , Inibidores Enzimáticos/farmacologia , Humanos , Espectrometria de Massas , Proteínas/química , Proteínas/isolamento & purificação , Padrões de Referência , Espectrometria de Massas por Ionização por Electrospray
18.
J Nutr Sci Vitaminol (Tokyo) ; 53(3): 213-8, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17874825

RESUMO

We investigated the effects of zinc supplementation on clinical observations in chronic hepatitis C patients receiving pegylated interferon (PEG-IFN) alpha-2b plus ribavirin combination therapy. Patients were randomly allocated to receive 150 mg polaprezinc (zinc group, n=11) or no supplement (control group, n=12) daily in addition to PEG-IFN alpha-2b plus ribavirin therapy and 300 mg vitamin E and 600 mg vitamin C supplementation daily for 48 wk. Among the patients who continued treatment, the serum alanine aminotransferase (ALT) level at 12 wk in the zinc group was significantly lower than that in the control group. All patients in the zinc group (9/9) and 67% (8/12) of the control patients at 24 wk, and all patients in the zinc group (7/7) and 60% (6/10) of the control patients at 48 wk showed a decrease in serum ALT levels to within the normal range (7-44 U/L). HCV RNA disappeared in all patients (7/7) in the zinc group and in 8 of 10 control patients at 48 wk. Polaprezinc supplementation decreased plasma thiobarbituric acid reactive substances and prevented the decrease of polyunsaturated fatty acids of erythrocyte membrane phospholipids. No significant differences were observed in the dosage of medicines or other clinical data during the treatment. These observations indicate that polaprezinc supplementation may have induced some antioxidative functions in the liver which resulted in reduced hepatocyte injury during PEG-IFN alpha-2b plus ribavirin therapy.


Assuntos
Suplementos Nutricionais , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Ribavirina/uso terapêutico , Transaminases/efeitos dos fármacos , Zinco/uso terapêutico , Alanina Transaminase/sangue , Alanina Transaminase/efeitos dos fármacos , Antivirais/uso terapêutico , Ácido Ascórbico/administração & dosagem , Carnosina/administração & dosagem , Carnosina/análogos & derivados , Carnosina/uso terapêutico , Quimioterapia Combinada , Ácidos Graxos Insaturados/metabolismo , Feminino , Citometria de Fluxo , Humanos , Interferon alfa-2 , Masculino , Pessoa de Meia-Idade , Compostos Organometálicos/administração & dosagem , Compostos Organometálicos/uso terapêutico , Polietilenoglicóis , Proteínas Recombinantes , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo , Fatores de Tempo , Transaminases/sangue , Resultado do Tratamento , Vitamina E/administração & dosagem , Vitaminas/administração & dosagem , Zinco/administração & dosagem , Compostos de Zinco/administração & dosagem , Compostos de Zinco/uso terapêutico
19.
J Nutr Sci Vitaminol (Tokyo) ; 53(2): 153-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17616003

RESUMO

Nutrition may play an important role in the pathogenesis and treatment of ulcerative colitis. Several studies suggest an association between dietary factors and the onset of ulcerative colitis; however, only few studies have examined the relationship between dietary intake and relapse of ulcerative colitis. The aim of this study was to assess the dietary intake and antioxidative capacity of ulcerative colitis patients and to elucidate the efficacy of dietary therapy for ulcerative colitis. Dietary intake, fatty acid composition of phospholipids in plasma and neutrophils, serum fat-soluble vitamin levels, and oxygen radical absorbance capacity were analyzed in 29 ulcerative colitis patients (7 males and 22 females), who were treated at the Department of Gastroenterology, Okayama University Hospital. Total fat intake, fat energy ratio and linoleic acid intake were significantly lower, while protein and carbohydrate intakes were significantly higher, in the patients than age- and sex-matched controls. In the neutrophil phospholipids of ulcerative colitis patients, significantly higher levels of linoleic aicd and arachidonic acid and a lower level of eicosapentaenoic acid were observed. The concentrations of serum retinol and beta-carotene but not alpha-tocopherol were significantly lower and serum oxygen radical absorbance capacity was also lower than in the controls. Significant correlations between serum oxygen radical absorbance capacity and retinol (r = 0.567, p = 0.0031), alpha-tocopherol (r = 0.560, p = 0.0036) and beta-carotene (r = 0.440, p = 0.0279) concentrations were observed in the ulcerative colitis patients. A diet restricting the intake of linoleic acid and supplemented with eicosapentaenoic acid and antioxidative vitamins may be recommendable for the nutritional management of ulcerative colitis patients.


Assuntos
Antioxidantes/metabolismo , Colite Ulcerativa/metabolismo , Dieta/métodos , Ácidos Graxos/metabolismo , Neutrófilos/metabolismo , Espécies Reativas de Oxigênio/metabolismo , Vitaminas/sangue , Adulto , Albuminas/metabolismo , Antioxidantes/análise , Registros de Dieta , Feminino , Humanos , Masculino , Fosfolipídeos/metabolismo , Proteínas/metabolismo , Vitamina A/sangue , alfa-Tocoferol/sangue , beta Caroteno/sangue
20.
Am J Physiol Cell Physiol ; 293(2): C705-11, 2007 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-17475661

RESUMO

Polyamines are small cationic molecules required for cellular proliferation. Agmatine is a biogenic amine unique in its capacity to arrest proliferation in cell lines by depleting intracellular polyamine levels. We previously demonstrated that agmatine enters mammalian cells via the polyamine transport system. As polyamine transport is positively correlated with the rate of cellular proliferation, the current study examines the antiproliferative effects of agmatine on cells with varying proliferative kinetics. Herein, we evaluate agmatine transport, intracellular accumulation, and its effects on antizyme expression and cellular proliferation in nontransformed cell lines and their transformed variants. H-ras- and Src-transformed murine NIH/3T3 cells (Ras/3T3 and Src/3T3, respectively) that were exposed to exogenous agmatine exhibit increased uptake and intracellular accumulation relative to the parental NIH/3T3 cell line. Similar increases were obtained for human primary foreskin fibroblasts relative to a human fibrosarcoma cell line, HT1080. Agmatine increases expression of antizyme, a protein that inhibits polyamine biosynthesis and transport. Ras/3T3 and Src/3T3 cells demonstrated augmented increases in antizyme protein expression relative to NIH/3T3 in response to agmatine. All transformed cell lines were significantly more sensitive to the antiproliferative effects of agmatine than nontransformed lines. These effects were attenuated in the presence of exogenous polyamines or inhibitors of polyamine transport. In conclusion, the antiproliferative effects of agmatine preferentially target transformed cell lines due to the increased agmatine uptake exhibited by cells with short cycling times.


Assuntos
Agmatina/metabolismo , Proliferação de Células , Fibroblastos/metabolismo , Biossíntese de Proteínas , Proteínas/metabolismo , Agmatina/farmacologia , Animais , Ligação Competitiva , Proteínas de Transporte/antagonistas & inibidores , Proteínas de Transporte/metabolismo , Linhagem Celular Transformada , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Relação Dose-Resposta a Droga , Fibroblastos/efeitos dos fármacos , Fibroblastos/enzimologia , Genes ras , Genes src , Humanos , Cinética , Camundongos , Células NIH 3T3 , Ornitina Descarboxilase/metabolismo , Biossíntese de Proteínas/efeitos dos fármacos , Putrescina/metabolismo
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...