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1.
Br J Cancer ; 130(3): 496-503, 2024 02.
Artigo em Inglês | MEDLINE | ID: mdl-38114529

RESUMO

BACKGROUND: Weight cycling is the repeated episodes manifesting intentional weight loss and subsequent unintentional weight gain. Whether the frequency and magnitude of weight cycling is associated with colorectal cancer risk independent of body mass index (BMI) remains unknown. METHODS: Two prospective cohort studies, Nurses' Health Study I and Health Professionals Follow-up Study, followed 85,562 participants from 1992 to 2014. Participants completed a questionnaire regarding the frequency and magnitude of intentional weight loss in the past 4 years at the baseline. Hazard ratios (HRs) and 95% confidence intervals (CIs) were estimated using Cox proportional hazard model. RESULTS: We identified 1626 colorectal cancer cases during up to 22 years of follow-up. In the pooled analysis of HPFS and NHS, compared to non-weight cycling, moderate weight cycling (≥3 times of intentional weight loss of ≥2.3-4.4 kg) was associated with a reduced risk of colorectal cancer after adjustment for confounders, including attained BMI after weight cycling (HR = 0.82, 95% CI 0.69, 0.97). However, no significant association was observed in mild weight cyclers and in severe weight cyclers. CONCLUSIONS: Moderate weight cycling was associated with a lower risk of colorectal cancer independent of BMI. This finding needs further studies for replication and putative biological mechanisms.


Assuntos
Neoplasias Colorretais , Ciclo de Peso , Humanos , Estudos Prospectivos , Seguimentos , Fatores de Risco , Redução de Peso , Índice de Massa Corporal , Neoplasias Colorretais/epidemiologia , Neoplasias Colorretais/etiologia
2.
FASEB J ; 34(9): 11786-11801, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32692906

RESUMO

The TNF-related apoptosis-inducing ligand (TRAIL) triggers apoptosis in cells by signaling through the O-glycosylated death receptors (DR4 and DR5), but the sensitivity to TRAIL-induced apoptosis of cells varies, and the attributes of this phenomenon are complex. Human carcinoma cells often express truncated O-glycans, Tn (GalNAcα1-Ser/Thr), and Sialyl-Tn (Siaα2-6GalNAcα1-Ser/Thr, STn) on their surface glycoproteins, yet molecular mechanisms in terms of advantages for tumor cells to have these truncated O-glycans remain elusive. Normal extended O-glycan biosynthesis is regulated by a specific molecular chaperone Cosmc through assisting of the correct folding of Core 1 ß3 Galactosyltransferase (T-synthase). Here, we use tumor cell lines harboring mutations in Cosmc, and therefore expressing Tn and STn antigens to study the role of O-glycans in TRAIL-induced apoptosis. Expression of Tn and STn in tumor cells attenuates their sensitivity to TRAIL treatment; when transfected with wild-type Cosmc, these tumor cells thus express normal extended O-glycans and become more sensitive to TRAIL treatment. Mechanistically, Tn/STn antigens impair homo-oligomerization and stability of DR4 and DR5. These results represent the first mechanistic insight into how O-glycan structures on cell surface modulate their sensitivity to apoptotic stimuli, suggesting expression of Tn/STn may offer tumor cell survival advantages through altering DR4 and/or DR5 activity.


Assuntos
Apoptose/efeitos dos fármacos , Polissacarídeos/metabolismo , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Antígenos Glicosídicos Associados a Tumores/metabolismo , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/genética , Glicosilação , Humanos , Células Jurkat , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Mutação , Polissacarídeos/química , Multimerização Proteica/efeitos dos fármacos , Estabilidade Proteica/efeitos dos fármacos , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/química , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/genética
3.
J Biol Chem ; 293(50): 19277-19289, 2018 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-30315103

RESUMO

Influenza viruses cause contagious respiratory infections, resulting in significant economic burdens to communities. Production of influenza-specific Igs, specifically IgGs, is one of the major protective immune mechanisms against influenza viruses. In humans, N-glycosylation of IgGs plays a critical role in antigen binding and effector functions. The ferret is the most commonly used animal model for studying influenza pathogenesis, virus transmission, and vaccine development, but its IgG structure and functions remain largely undefined. Here we show that ferret IgGs are N-glycosylated and that their N-glycan structures are diverse. Using a comprehensive strategy based on MS and ultra-HPLC analyses in combination with exoglycosidase digestions, we assigned 42 N-glycan structures in ferret IgGs. We observed that N-glycans of ferret IgGs consist mainly of complex-type glycans, including some high-mannose and hybrid glycans, similar to those observed in human IgG. The complex-type glycans of ferret IgGs were primarily core-fucosylated. Furthermore, a fraction of N-glycans carried bisecting GlcNAc. Ferret IgGs also had a minor fraction of glycans carrying α2-6Neu5Ac(s). We noted that, unlike human IgG, ferret IgGs have αGal epitopes on some N-glycans. Interestingly, influenza A infection caused prominent changes in the N-glycans of ferret IgG, mainly because of an increase in bisecting GlcNAc and F1A2G0 and a corresponding decrease in F1A2G1. This suggests that the glycosylation of virus-specific IgG may play a role in its functionality. Our study highlights the need to further elucidate the structure-function relationships of IgGs in universal influenza vaccine development.


Assuntos
Furões , Imunoglobulina G/metabolismo , Vírus da Influenza A/fisiologia , Infecções por Orthomyxoviridae/imunologia , Polissacarídeos/metabolismo , Acetilglucosamina/metabolismo , Animais , Glicosilação , Glicoproteínas de Hemaglutininação de Vírus da Influenza/metabolismo , Imunoglobulina G/química , Imunoglobulina G/imunologia , Masculino , Polissacarídeos/química
4.
Drug Resist Updat ; 19: 13-21, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25840763

RESUMO

TNF-related apoptosis inducing ligand (TRAIL) selectively induces apoptosis in cancer cells without harming most normal cells. Currently, multiple clinical trials are underway to evaluate the antitumor activity of recombinant human TRAIL (rhTRAIL) and agonistic antibodies that target death receptors (DRs) 4 or 5. It is encouraging that these products have shown a tolerated safety profile in early phase studies. However, their therapeutic potential is likely limited by the emergence of tumor drug resistance phenomena. Increasing evidence indicates that TRAIL DRs are deficient on the plasma membrane of some cancer cells despite their total protein expression. Notably, the lack of surface DR4/DR5 is sufficient to render cancers resistant to TRAIL-induced apoptosis, regardless of the status of other apoptosis signaling components. The current review highlights recent findings on the dynamic expression of TRAIL death receptors, including the regulatory roles of endocytosis, autophagy, and Ras GTPase-mediated signaling events. This information could aid in the identification of novel predictive biomarkers of tumor response as well as the development of combinational drugs to overcome or bypass tumor drug resistance to TRAIL receptor-targeted therapies.


Assuntos
Neoplasias/tratamento farmacológico , Receptores do Ligante Indutor de Apoptose Relacionado a TNF/metabolismo , Ligante Indutor de Apoptose Relacionado a TNF/farmacologia , Antineoplásicos/efeitos adversos , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Biomarcadores Tumorais/metabolismo , Desenho de Fármacos , Resistencia a Medicamentos Antineoplásicos , Humanos , Neoplasias/patologia , Proteínas Recombinantes/farmacologia , Ligante Indutor de Apoptose Relacionado a TNF/efeitos adversos , Ligante Indutor de Apoptose Relacionado a TNF/metabolismo
5.
Korean J Physiol Pharmacol ; 19(4): 327-34, 2015 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-26170736

RESUMO

The cytoprotective enzyme heme oxygenase-1 (HO-1) influences endothelial cell survival, proliferation, inflammatory response, and angiogenesis in response to various angiogenic stimuli. In this study, we investigate the involvement of HO-1 in the angiogenic activity of orexin-A. We showed that orexin-A stimulates expression and activity of HO-1 in human umbilical vein endothelial cells (HUVECs). Furthermore, we showed that inhibition of HO-1 by tin (Sn) protoporphryin-IX (SnPP) reduced orexin-A-induced angiogenesis in vivo and ex vivo. Orexin-A-stimulated endothelial tube formation and chemotactic activity were also blocked in SnPP-treated vascular endothelial cells. Orexin-A treatment increased the expression of nuclear factor erythroid-derived 2 related factor 2 (Nrf2), and antioxidant response element (ARE) luciferase activity, leading to induction of HO-1. Collectively, these findings indicate that HO-1 plays a role as an important mediator of orexin-A-induced angiogenesis, and provide new possibilities for therapeutic approaches in pathophysiological conditions associated with angiogenesis.

6.
Inflamm Res ; 62(2): 145-54, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23064654

RESUMO

OBJECTIVE: Porphyromonas gingivalis is a major periodontopathogen that plays a role in the pathogenesis of periodontal disease. In this study, we investigated the effect of 18alpha-glycyrrhetinic acid (18α-GA), a natural triterpenoid compound derived from licorice root extract, on P. gingivalis lipopolysaccharide (LPS)-induced vascular permeability, which is a hallmark of inflammatory diseases such as periodontitis. METHODS: The inhibitory effects of 18α-GA on endothelial permeability were determined by measuring in vivo and in vitro endothelial permeability. Endothelial cells were pretreated with 18α-GA before exposure to P. gingivalis LPS, and total RNA or proteins were extracted and analyzed by reverse transcription polymerase chain reaction or western blotting. RESULTS: Porphyromonas gingivalis LPS-induced endothelial permeability was significantly inhibited by 18α-GA both in vivo and in vitro. 18α-GA reduces P. gingivalis LPS-induced gap formation of endothelial cells. Importantly, 18α-GA modulated the expression and secretion of interleukin-8 (IL-8), a key inducer of vascular permeability, by downregulating nuclear factor-κB (NF-κB). 18α-GA suppressed P. gingivalis LPS-stimulated inhibitor of kappa B (IκB) kinase activation, IκBα phosphorylation, and nuclear translocation of NF-κB. CONCLUSIONS: Overall, these findings suggest that 18α-GA significantly reduces P. gingivalis LPS-induced vascular permeability by repressing NF-κB-dependent endothelial IL-8 production, suggesting its therapeutic potential in P. gingivalis-related vascular diseases.


Assuntos
Permeabilidade Capilar/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Ácido Glicirretínico/farmacologia , Lipopolissacarídeos , Porphyromonas gingivalis , Células Cultivadas , Células Endoteliais/metabolismo , Humanos , Interleucina-8/metabolismo , NF-kappa B/metabolismo
7.
Biochem Biophys Res Commun ; 418(4): 662-8, 2012 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-22293189

RESUMO

Thromboxane synthase (TXAS) is an enzyme that catalyzes the synthesis of thromboxane A(2) (TXA(2)). Overexpression of TXAS is associated with a variety of vascular diseases. Recently, we reported that visfatin, a novel adipokine, exhibits angiogenic actions. In this study, we showed that visfatin increased mRNA and protein levels of TXAS and stimulated TXA(2) biosynthesis in vascular endothelial cells. In addition, visfatin induced the expression and secretion of interleukin-8 (IL-8), which is blocked by a TXAS inhibitor and by the transfection of siRNA specific for TXAS. Furthermore, the inhibition of TXAS activity and blockade of the IL-8 receptor attenuated visfatin-induced endothelial angiogenesis. Together, these results showed that visfatin promoted IL-8 production by upregulation of TXAS, leading to angiogenic activation in endothelial cells.


Assuntos
Endotélio Vascular/metabolismo , Regulação da Expressão Gênica , Interleucina-8/genética , Neovascularização Fisiológica/genética , Nicotinamida Fosforribosiltransferase/metabolismo , Tromboxano A2/biossíntese , Tromboxano-A Sintase/genética , Linhagem Celular Tumoral , Humanos , Regulação para Cima
8.
Biochim Biophys Acta ; 1803(11): 1244-51, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20691219

RESUMO

Thymosin ß4 has multi-functional roles in cell physiology, but little is known about its mechanism(s) of action. We previously reported that thymosin ß4 stimulated angiogenesis through the induction of vascular endothelial growth factor (VEGF). To identify the mechanism of VEGF induction by thymosin ß4, we have used a luciferase assay system with VEGF in the 5' promoter region. We also analyzed the effect of thymosin ß4 on VEGF mRNA stability and on the expression and stability of hypoxia-inducible factor (HIF)-1α. We found that thymosin ß4 induces VEGF expression by an increase in the stability of HIF-1α protein. Analysis of the expression patterns of thymosin ß4 and HIF-1α in colon cancer tissue microarray showed that thymosin ß4 and HIF-1α co-localized in these biopsies. These data show that thymosin ß4 induces the expression of VEGF indirectly by increasing the protein stability of HIF-1α.


Assuntos
Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Subunidade alfa do Fator 1 Induzível por Hipóxia/genética , Timosina/farmacologia , Fator A de Crescimento do Endotélio Vascular/genética , Animais , Biópsia , Western Blotting , Linhagem Celular Tumoral , Colo/metabolismo , Colo/patologia , Neoplasias do Colo/genética , Neoplasias do Colo/metabolismo , Neoplasias do Colo/patologia , Feminino , Humanos , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Imuno-Histoquímica , Luciferases/genética , Luciferases/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microscopia Confocal , Regiões Promotoras Genéticas/genética , Estabilidade Proteica/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Timosina/genética , Timosina/metabolismo , Análise Serial de Tecidos , Fator A de Crescimento do Endotélio Vascular/metabolismo
9.
Biochim Biophys Acta ; 1793(11): 1759-67, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19751774

RESUMO

Signal transducer and activator of transcription 3 (STAT3) acts as a mediator and biomarker in endothelial activation. We have recently shown that a novel adipokine visfatin promotes endothelial angiogenesis. The present study was to determine whether visfatin affects STAT3 activity and to explore the potential target gene(s). Here, we found that visfatin induced the activation of STAT3, as characterized by increased tyrosine phosphorylation, nuclear translocation, and DNA-binding activity in human endothelial cells. In addition, visfatin significantly upregulated mRNA and protein levels of endothelial interleukin-6 (IL-6), which was blocked by a specific inhibitor of STAT3 signaling and by the transfection of siRNA specific for STAT3. Furthermore, visfatin-induced angiogenesis was reduced by the inhibition of STAT3 signaling or neutralization of IL-6 function, as measured by tube formation, rat aortic ring assay, and mouse Matrigel plug assay. Taken together, our results provide the first example of STAT3-dependent endothelial IL-6 induction by visfatin and of the role of IL-6 in mediating visfatin-induced angiogenesis.


Assuntos
Citocinas/metabolismo , Endotélio Vascular/metabolismo , Interleucina-6/biossíntese , Neovascularização Fisiológica/fisiologia , Nicotinamida Fosforribosiltransferase/metabolismo , Fator de Transcrição STAT3/metabolismo , Animais , Células Cultivadas , Citocinas/farmacologia , Endotélio Vascular/citologia , Humanos , Camundongos , Neovascularização Fisiológica/efeitos dos fármacos , Nicotinamida Fosforribosiltransferase/farmacologia , Ratos , Ratos Sprague-Dawley , Transdução de Sinais/efeitos dos fármacos , Transdução de Sinais/fisiologia
10.
Biochem Biophys Res Commun ; 403(1): 59-65, 2010 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-21040705

RESUMO

Orexin-A, a neuropeptide originally discovered in the hypothalamus, is found in peripheral organs, as well as in the central nervous system, and is involved in the regulation of food intake, energy homeostasis, and cardiovascular functions. In this study, we report that orexin-A induces invivo neovascularization in a mouse Matrigel plug and ex vivo sprouting of endothelial cells in rat aortic rings. We also show that orexin-A increases migration and tube formation in human umbilical vein endothelial cells (HUVECs), and this effect is mediated by orexin receptors on endothelial cells. Moreover, orexin-A activates the extracellular signal-regulated kinase 1/2 (ERK1/2) in HUVECs, which is closely linked to angiogenic responses. The inhibition of ERK activation significantly suppresses orexin-A-stimulated endothelial angiogenesis. Taken together, our results indicate that orexin-A functions as a new proangiogenic peptide and requires MEK/ERK-dependent pathway for its angiogenic actions. These results suggest orexin-A and its receptor may act as important modulators of angiogenesis under pathophysiological conditions.


Assuntos
Células Endoteliais/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/biossíntese , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Neovascularização Fisiológica , Neuropeptídeos/fisiologia , Animais , Células Cultivadas , Quimiotaxia/efeitos dos fármacos , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/enzimologia , Humanos , Peptídeos e Proteínas de Sinalização Intracelular/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Neuropeptídeos/farmacologia , Orexinas , Ratos
11.
Biochem Biophys Res Commun ; 397(3): 413-9, 2010 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-20510674

RESUMO

Thromboxane A(2) (TXA(2)), a major prostanoid formed from prostaglandin H(2) by thromboxane synthase, is involved in the pathogenesis of a variety of vascular diseases. In this study, we report that TXA(2) mimetic U46619 significantly increases the endothelial permeability both in vitro and in vivo. U46619 enhanced the expression and secretion of interleukin-8 (IL-8), a major inducer of vascular permeability, in endothelial cells. Promoter analysis showed that the U46619-induced expression of IL-8 was mainly regulated by nuclear factor-kappaB (NF-kappaB). U46619 induced the activation of NF-kappaB through IkappaB kinase (IKK) activation, IkappaB phosphorylation and NF-kappaB nuclear translocation. Furthermore, the inhibition of IL-8 or blockade of the IL-8 receptor attenuated the U46619-induced endothelial cell permeability by modulating the cell-cell junctions. Overall, these results suggest that U46619 promotes vascular permeability through the production of IL-8 via NF-kappaB activation in endothelial cells.


Assuntos
Permeabilidade Capilar , Endotélio Vascular/metabolismo , Interleucina-8/biossíntese , Tromboxano A2/metabolismo , Ácido 15-Hidroxi-11 alfa,9 alfa-(epoximetano)prosta-5,13-dienoico/farmacologia , Células Cultivadas , Endotélio Vascular/efeitos dos fármacos , Expressão Gênica/efeitos dos fármacos , Humanos , Proteínas I-kappa B/metabolismo , Interleucina-8/genética , NF-kappa B/metabolismo , Fosforilação , Regiões Promotoras Genéticas/efeitos dos fármacos , Transporte Proteico , Regulação para Cima
12.
Exp Cell Res ; 315(19): 3359-69, 2009 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-19703440

RESUMO

Neuromedin B (NMB) is one of the bombesin-like peptides in mammals. Recently, bombesin-like peptides have been characterized as growth factors in highly vascularized tumors. In this study, we report that NMB potently stimulates in vivo neovascularization in a mouse Matrigel plug and the sprouting of endothelial cells ex vivo in rat aortic rings. In addition, NMB increases the migration and tube formation in human umbilical vein endothelial cells (HUVECs). Moreover, treatment of HUVECs with NMB activates the extracellular signal-regulated kinase 1/2 (ERK(1/2)), Akt, and endothelial nitric oxide synthase (eNOS) and increases the level of NO production in a dose- and time-dependent manner. Furthermore, ERK activation and angiogenic sprouting in response to NMB are significantly blocked by the MEK inhibitor. Inhibition of phosphatidylinositol 3-kinase (PI3K) suppresses the NMB-stimulated tubular formation of HUVECs, along with reduction in the phosphorylation of Akt and eNOS. Taken together, these results indicate that NMB is a novel angiogenic peptide, and its angiogenic activity is mediated by activating the MEK/ERK- and PI3K/Akt/eNOS-dependent pathways. This study suggests that NMB may play important roles in mediating a variety of pathophysiological angiogenesis.


Assuntos
Células Endoteliais/fisiologia , MAP Quinases Reguladas por Sinal Extracelular/metabolismo , Neovascularização Fisiológica/efeitos dos fármacos , Neurocinina B/análogos & derivados , Proteínas Proto-Oncogênicas c-akt/metabolismo , Animais , Aorta/citologia , Células Endoteliais/metabolismo , Ativação Enzimática , Humanos , Camundongos , Camundongos Endogâmicos C57BL , Neurocinina B/farmacologia , Óxido Nítrico Sintase Tipo III/metabolismo , Fosfatidilinositol 3-Quinases/metabolismo , Ratos , Transdução de Sinais , Veias Umbilicais/citologia
13.
Biochim Biophys Acta ; 1779(12): 789-96, 2008 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-18760387

RESUMO

Drosophila big brain (bib) encodes for a protein similar to members of the major intrinsic protein family, which includes the water- and ion-conducting aquaporin (AQP) channels. In mammals, AQP dysregulation has been implicated in a variety of diseases, including colorectal cancer and colonic injury. However, the regulatory mechanisms of AQP expression remain to be clearly elucidated. In this study, as we found a DREF binding site (DRE) in the 5'-flanking regions of both the Drosophila bib gene and the human AQP1 gene, we assessed the role of DREF in bib gene expression. DREF in Drosophila and humans has been demonstrated to function as a key transcriptional activator for cell proliferation-related genes. Herein, we demonstrate that the DRE is required for optimal promoter activity of Drosophila bib gene, particularly in the larval imaginal discs, which are actively proliferating tissues, as well as the adult hindgut. Our results may provide insight into the mechanisms inherent to the regulation of mammalian AQP genes.


Assuntos
Aquaporinas/metabolismo , Proteínas de Drosophila/genética , Proteínas de Drosophila/fisiologia , Proteínas de Membrana/genética , Proteínas de Membrana/fisiologia , Fatores de Transcrição/fisiologia , Animais , Animais Geneticamente Modificados , Aquaporina 1/metabolismo , Núcleo Celular/metabolismo , Drosophila melanogaster , Regulação da Expressão Gênica , Humanos , Íons , Modelos Biológicos , Mutagênese Sítio-Dirigida , Regiões Promotoras Genéticas , Fatores de Transcrição/genética , Água/química
14.
Biochim Biophys Acta ; 1783(5): 886-95, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18241674

RESUMO

Visfatin has recently been identified as a novel visceral adipokine which may be involved in obesity-related vascular disorders. However, it is not known whether visfatin directly contributes to endothelial dysfunction. Here, we investigated the effect of visfatin on vascular inflammation, a key step in a variety of vascular diseases. Visfatin induced leukocyte adhesion to endothelial cells and the aortic endothelium by induction of the cell adhesion molecules, ICAM-1 and VCAM-1. Promoter analysis revealed that visfatin-mediated induction of CAMs is mainly regulated by nuclear factor-kappaB (NF-kappaB). Visfatin stimulated IkappaBalpha phosphorylation, nuclear translocation of the p65 subunit of NF-kappaB, and NF-kappaB DNA binding activity in HMECs. Furthermore, visfatin increased ROS generation, and visfatin-induced CAMs expression and NF-kappaB activation were abrogated in the presence of the direct scavenger of ROS. Taken together, our results demonstrate that visfatin is a vascular inflammatory molecule that increases expression of the inflammatory CAMs, ICAM-1 and VCAM-1, through ROS-dependent NF-kappaB activation in endothelial cells.


Assuntos
Endotélio Vascular/metabolismo , Molécula 1 de Adesão Intercelular/genética , NF-kappa B/metabolismo , Nicotinamida Fosforribosiltransferase/farmacologia , Espécies Reativas de Oxigênio/metabolismo , Molécula 1 de Adesão de Célula Vascular/genética , Adesão Celular , Células Cultivadas , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Endotélio Vascular/citologia , Endotélio Vascular/enzimologia , Expressão Gênica , Humanos , Molécula 1 de Adesão Intercelular/metabolismo , Leucócitos/imunologia , NADPH Oxidases/metabolismo , Regiões Promotoras Genéticas , Molécula 1 de Adesão de Célula Vascular/metabolismo
15.
Biochem Biophys Res Commun ; 379(2): 206-11, 2009 Feb 06.
Artigo em Inglês | MEDLINE | ID: mdl-19100714

RESUMO

Adipokines have been known to act as angiogenic regulators in the process of angiogenesis. Recently, we have demonstrated that visfatin, a novel adipokine, has angiogenic activity. However, little has been reported on the underlying mechanism of visfatin-induced angiogenesis. In this study, we report that visfatin-induced angiogenesis is mediated by endothelial fibroblast growth factor-2 (FGF-2). Visfatin increased the levels of FGF-2 mRNA and protein in human endothelial cells. The enhancement in FGF-2 expression was prevented by an inhibitor of the extracellular signal-regulated kinase 1/2 (Erk1/2) pathway. Furthermore, visfatin-induced angiogenesis was reduced by inhibition of FGF-2 receptor kinase or by neutralization of FGF-2 function. Taken together, our results indicate that visfatin-induced endothelial angiogenesis is composed largely of two sequential steps: the induction of Erk1/2-dependent FGF-2 gene expression by visfatin and the subsequent FGF-2-induced angiogenesis. These data further suggest an integral role for visfatin-FGF-2 signaling axis in modulating endothelial angiogenesis.


Assuntos
Citocinas/metabolismo , Endotélio Vascular/enzimologia , Fator 2 de Crescimento de Fibroblastos/metabolismo , Neovascularização Fisiológica , Nicotinamida Fosforribosiltransferase/metabolismo , Animais , Fator 2 de Crescimento de Fibroblastos/genética , Humanos , Masculino , Proteína Quinase 1 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/antagonistas & inibidores , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Inibidores de Proteínas Quinases , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Regulação para Cima
16.
Biochem Biophys Res Commun ; 387(2): 342-7, 2009 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-19595669

RESUMO

Aspirin has been reported to induce apoptosis in various cancer cell lines. However, the apoptotic effects of aspirin on human brain tumor cells are not well understood. Here, we have assessed the effect of aspirin on human gliobalstoma cell line A172 and found that aspirin induced the apoptosis of A172 cells, as determined by TUNEL assay, FACS analysis, and Hoechst staining. The underlying mechanism of this effect consists of reduction in the level of phosphorylated STAT3 (Tyr705), a transcription factor required for survival of A172 cells. Moreover, the expression of STAT3 target genes such as Cyclin D1, XIAP, and Bcl-2 that are essential for cell growth and survival was apparently attenuated after aspirin treatment. We also showed that the expression and secretion of interleukin-6 (IL-6), leading to STAT3 phosphorylation, was inhibited by aspirin. When administered exogenous IL-6 to aspirin-treated A172 cells, the phosphorylation of STAT3 and cellular apoptosis were restrained compared to aspirin only-treated cells. Taken together, our results indicate that aspirin causes apoptosis via down-regulation of IL-6-dependent STAT3 signaling, suggesting that aspirin could be therapeutically useful for a potential anti-glioblastoma therapeutic approach.


Assuntos
Antineoplásicos/farmacologia , Apoptose , Aspirina/farmacologia , Glioblastoma/metabolismo , Interleucina-6/antagonistas & inibidores , Fator de Transcrição STAT3/antagonistas & inibidores , Antineoplásicos/antagonistas & inibidores , Aspirina/antagonistas & inibidores , Linhagem Celular Tumoral , Humanos , Interleucina-6/farmacologia , Fosforilação/efeitos dos fármacos , Transdução de Sinais/efeitos dos fármacos , Tirosina/metabolismo
17.
Arch Pharm Res ; 32(4): 583-91, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19407977

RESUMO

P. gingivalis is a major pathogen that is involved in the onset and progression of periodontal disease. This study investigated the effect of resveratrol, a naturally occurring polyphenol, on P. gingivalis LPS-accelerated vascular inflammation, a key step in the progression of periodontitis. Resveratrol significantly inhibited the P. gingivalis LPS-induced adhesion of leukocytes to endothelial cells and to the aortic endothelium by down-regulating the cell adhesion molecules, ICAM-1 and VCAM-1. Moreover, the inhibition of the P. gingivalis LPS-induced cell adhesion molecules by resveratrol was mainly mediated by nuclear factor-kappaB (NF-kappaB). Resveratrol suppressed P. gingivalis LPS-stimulated IkappaBalpha phosphorylation and nuclear translocation of the p65 subunit of NF-kappaB in HMECs. Overall, these findings suggest that resveratrol significantly attenuates the P. gingivalis LPS-induced monocyte adhesion to the endothelium by suppressing the expression of the NF-kappaB-dependent cell adhesion molecules, suggesting its therapeutic role in periodontal pathogen-induced vascular inflammation.


Assuntos
Anti-Inflamatórios/farmacologia , Células Endoteliais/efeitos dos fármacos , Molécula 1 de Adesão Intercelular/metabolismo , Lipopolissacarídeos/farmacologia , Porphyromonas gingivalis/patogenicidade , Estilbenos/farmacologia , Fator de Transcrição RelA/metabolismo , Molécula 1 de Adesão de Célula Vascular/metabolismo , Animais , Adesão Celular/efeitos dos fármacos , Relação Dose-Resposta a Droga , Células Endoteliais/imunologia , Humanos , Proteínas I-kappa B/metabolismo , Molécula 1 de Adesão Intercelular/genética , Leucócitos/efeitos dos fármacos , Leucócitos/imunologia , Lipopolissacarídeos/isolamento & purificação , Masculino , Inibidor de NF-kappaB alfa , Fosforilação , Porphyromonas gingivalis/química , RNA Mensageiro/metabolismo , Ratos , Ratos Sprague-Dawley , Resveratrol , Transcrição Gênica/efeitos dos fármacos , Células U937 , Molécula 1 de Adesão de Célula Vascular/genética
18.
Chin J Integr Med ; 25(5): 378-385, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-29700763

RESUMO

OBJECTIVE: To classify the evaluation methods for amount of tongue coating (TC) and investigate their reliability, accuracy, and frequency of use. METHODS: Articles published from 1985 to 2015 were searched for evaluation methods for the amount of TC in PubMed and the Cochrane Library. Only clinical researches were included except protocol articles. The methods were classified according to their characteristics. RESULTS: Finally, 113 articles were selected. The evaluation method for the amount of TC from the articles was classified into 4 types: intuitive, specificative, computerized, and weighing TC. The reliability in the intuitive and specificative methods (κ =0.33-0.92) showed varying levels among the studies. In general, the amount of TC calculated by the specificative method (Spearman's r=0.68-0.80) was more strongly related to the directly measured value than to the value estimated by the computerized method (Pearson's r=0.442). The number of articles published on this topic has increased consistently, and the specificative method was the most frequently used. Despite the higher reliability of the computerized method, it has not been widely used. CONCLUSIONS: The high prevalence of the specificative method would continue in clinical practice because of its convenience and accuracy. However, to establish higher reliability, the limitation of the subjectivity of the assessors should be overcome through calibration training. In the computerized method, novel algorithms are needed to obtain a higher accuracy so that it can help the practitioners confidently estimate the amount of TC.


Assuntos
Medicina Tradicional Chinesa/métodos , Língua/fisiologia , Humanos , Reprodutibilidade dos Testes
19.
Artigo em Inglês | MEDLINE | ID: mdl-31534469

RESUMO

OBJECTIVES: Acupuncture is often used for relieving symptoms of fibromyalgia syndrome (FMS). Our aim is to ascertain whether verum acupuncture is more effective than sham acupuncture in FMS. METHODS: We collected RCTs to investigate the effects of verum acupuncture and sham acupuncture on pain, sleep quality, fatigue, and general status in FMS patients. The databases used for data retrieval were PubMed, Central Cochrane, EMBASE, PsycINFO, CNKI, VIP, OASIS, KoreaMed, and RISS. Selection/exclusion from the retrieved records was performed according to prespecified criteria, and the final selected records were assessed according to the Cochrane risk of bias tool. The results of the included trials were synthesized on the basis of outcomes, and subgroup analysis depended on the type of add-on sham acupuncture that was performed. RESULTS: Ten RCTs (690 participants) were eligible, and eight RCTs were eventually included in the meta-analysis. The synthesis showed a sizable effect of verum acupuncture compared with sham acupuncture on pain relief (standardized mean difference (SMD) -0.49, Z = 3.26, P=0.001; I 2 = 59%), improving sleep quality (SMD -0.46, Z = 3.24, P=0.001; I 2 = 0%), and reforming general status (SMD -0.69, Z = 6.27, P < 0.00001; I 2 = 4%). However, efficacy on fatigue was insignificant (SMD -0.10, Z = 0.51, P=0.61; I 2 = 46%). When compared with a combination of simulation and improper location of needling, the effect of verum acupuncture for pain relief was the most obvious. CONCLUSIONS: Verum acupuncture is more effective than sham acupuncture for pain relief, improving sleep quality, and reforming general status in FMS posttreatment. However, evidence that it reduces fatigue was not found.

20.
Biochim Biophys Acta ; 1763(3): 282-9, 2006 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-16516312

RESUMO

The marked induction of glial fibrillary acidic protein (GFAP) has been observed in astrocytes during neuropathological processes accompanying reactive gliosis; however, the precise molecular mechanism(s) underlying this GFAP induction remains poorly resolved. Therefore, in this study, we examined whether the change of nuclear factor-kappa B (NF-kappaB) activity can influence GFAP expression levels. Aspirin, widely used to prevent NF-kappaB activity, reduced the levels of GFAP mRNA and protein in human astroglial cells including human glioblastoma A172 cells and primary human brain astrocyte cells (HBAs). Furthermore, aspirin inhibited the effects of hypoxic injury on the up-regulation of GFAP expression in HBAs. We confirmed the repressive effect of aspirin on GFAP transcription by GFAP promoter-driven reporter assay and found that one NF-kappaB binding site conserved in the mouse and human GFAP gene promoters is critical for this effect. To further delineate whether NF-kappaB is directly involved in the regulation of GFAP gene expression, we transfected A172 cells with an expression vector encoding a super-repressor IkappaBalpha protein (IkappaBalpha-SR) to specifically inhibit NF-kappaB activity and found the marked reduction of GFAP protein levels in IkappaBalpha-SR-transfectant cells. Taken together, our results suggest that NF-kappaB may play pivotal roles in GFAP gene expression.


Assuntos
Aspirina/farmacologia , Astrócitos/efeitos dos fármacos , Astrócitos/metabolismo , Proteína Glial Fibrilar Ácida/genética , Proteína Glial Fibrilar Ácida/metabolismo , NF-kappa B/antagonistas & inibidores , Regulação para Cima/efeitos dos fármacos , Astrócitos/citologia , Hipóxia Celular/efeitos dos fármacos , Regulação para Baixo/genética , Humanos , Quinase I-kappa B/metabolismo , NF-kappa B/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transcrição Gênica/efeitos dos fármacos , Células Tumorais Cultivadas
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