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1.
Front Biosci (Landmark Ed) ; 23(5): 852-864, 2018 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-28930576

RESUMO

The antioxidants such as polyphenols, especially flavonols, present in large quantitites in cocoa, cause vasodilation, modulate inflammatory markers and cardiovascular health, and possess a range of protective cardiovascular effects. On the other hand, overconsumption of chocolate can lead to tachyarrhythmias, supraventricular tachycardia, atrial fibrillation, ventricular tachycardia and ventricular fibrillation due to its caffeine content. This review describes both the cardioprotective and adverse effects of chocolate and its constituents.


Assuntos
Antioxidantes/administração & dosagem , Cacau/química , Cardiotônicos/administração & dosagem , Chocolate , Polifenóis/administração & dosagem , Arritmias Cardíacas/etiologia , Arritmias Cardíacas/fisiopatologia , Cafeína/efeitos adversos , Estimulantes do Sistema Nervoso Central/efeitos adversos , Humanos
2.
Nutrients ; 9(5)2017 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-28531112

RESUMO

Cardiovascular diseases are the main cause of mortality and morbidity in the world. Hypertension, ischemia/reperfusion, diabetes and anti-cancer drugs contribute to heart failure through oxidative and nitrosative stresses which cause cardiomyocytes nuclear and mitochondrial DNA damage, denaturation of intracellular proteins, lipid peroxidation and inflammation. Oxidative or nitrosative stress-mediated injury lead to cardiomyocytes apoptosis or necrosis. The reactive oxygen (ROS) and nitrogen species (RNS) concentration is dependent on their production and on the expression and activity of anti-oxidant enzymes. Polyphenols are a large group of natural compounds ubiquitously expressed in plants, and epidemiological studies have shown associations between a diet rich in polyphenols and the prevention of various ROS-mediated human diseases. Polyphenols reduce cardiomyocytes damage, necrosis, apoptosis, infarct size and improve cardiac function by decreasing oxidative stress-induced production of ROS or RNS. These effects are achieved by the ability of polyphenols to modulate the expression and activity of anti-oxidant enzymes and several signaling pathways involved in cells survival. This report reviews current knowledge on the potential anti-oxidative effects of polyphenols to control the cardiotoxicity induced by ROS and RNS stress.


Assuntos
Miócitos Cardíacos/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Polifenóis/farmacologia , Animais , Humanos , Polifenóis/química , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo
3.
Exp Biol Med (Maywood) ; 242(10): 1079-1085, 2017 05.
Artigo em Inglês | MEDLINE | ID: mdl-27909015

RESUMO

Adipose tissue dysfunction represents a hallmark of diabetic patients and is a consequence of the altered homeostasis of this tissue. Mesenchymal stem cells (MSCs) and their differentiation into adipocytes contribute significantly in maintaining the mass and function of adult adipose tissue. The aim of this study was to evaluate the differentiation of MSCs from patients suffering type 2 diabetes (dASC) and how such process results in hyperplasia or rather a stop of adipocyte turnover resulting in hypertrophy of mature adipocytes. Our results showed that gene profile of all adipogenic markers is not expressed in diabetic cells after differentiation indicating that diabetic cells fail to differentiate into adipocytes. Interestingly, delta like 1, peroxisome proliferator-activated receptor alpha, and interleukin 1ß were upregulated whereas Sirtuin 1 and insulin receptor substrate 1 gene expression were found downregulated in dASC compared to cells obtained from healthy subjects. Taken together our data indicate that dASC lose their ability to differentiate into mature and functional adipocytes. In conclusion, our in vitro study is the first to suggest that diabetic patients might develop obesity through a hypertrophy of existing mature adipocytes due to failure turnover of adipose tissue. Impact statement In the present manuscript, we evaluated the differentiative potential of mesenchymal stem cells (MSCs) in adipocytes obtained from healthy and diabetic patients. This finding could be of great potential interest for the field of obesity in order to exploit such results to further understand the pathophysiological processes underlying metabolic syndrome. In particular, inflammation in diabetic patients causes a dysfunction in MSCs differentiation and a decrease in adipocytes turnover leading to insulin resistance.


Assuntos
Adipócitos/fisiologia , Tecido Adiposo/citologia , Diferenciação Celular , Diabetes Mellitus Tipo 2/patologia , Células-Tronco Mesenquimais/fisiologia , Perfilação da Expressão Gênica , Humanos
4.
Front Biosci (Landmark Ed) ; 22(5): 757-771, 2017 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-27814644

RESUMO

It has been shown that functional recovery of patients with acute congestive heart failure (ACHF) after treatment with conventional drugs (CD) is mediated by suppression of inflammation in peripheral blood mononuclear cells. Here, we analyzed gene expression profiles of monocytes from symptomatic ACHF patients (NYHA Class III-IV) before and after pharmacological treatment with CD. The treatment was associated with selective down-regulation of "TNFR signaling" and pro-inflammatory mediators CCL5, MIP-1α receptor, CD14, ITGAM, and significant up-regulation of "TNFR signaling" as evidenced by increase in anti-inflammatory factors including NF-kBIA, TNFAIP3 and SHP-1. In monocyte TNF-alpha-stimulated there is a down-regulation of the phosphatase SHP-1 which induces a significant activation of TAK-1/IKK/NF-kB signaling. These findings suggest that the therapeutic impact of CD treatment in symptomatic ACHF includes negative regulation of the NF-kB signaling in monocytes and the improvement of the SHP-1 activity.


Assuntos
Insuficiência Cardíaca/sangue , Monócitos/metabolismo , NF-kappa B/sangue , Proteína Tirosina Fosfatase não Receptora Tipo 6/sangue , Idoso , Estudos de Casos e Controles , Feminino , Insuficiência Cardíaca/genética , Humanos , Quinase I-kappa B/sangue , Linfócitos/metabolismo , MAP Quinase Quinase Quinases/sangue , Masculino , Pessoa de Meia-Idade , Neutrófilos/metabolismo , Proteína Tirosina Fosfatase não Receptora Tipo 6/antagonistas & inibidores , Proteína Tirosina Fosfatase não Receptora Tipo 6/genética , RNA Interferente Pequeno/genética , Transdução de Sinais , Transcriptoma , Fator de Necrose Tumoral alfa/sangue
5.
J Biol Chem ; 291(20): 10615-24, 2016 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-26987901

RESUMO

NEU3 sialidase has been shown to be a key player in many physio- and pathological processes, including cell differentiation, cellular response to hypoxic stress, and carcinogenesis. The enzyme, peculiarly localized on the outer leaflet of the plasma membrane, has been shown to be able to remove sialic acid residues from the gangliosides present on adjacent cells, thus creating cell to cell interactions. Nonetheless, herein we report that the enzyme localization is dynamically regulated between the plasma membrane and the endosomes, where a substantial amount of NEU3 is stored with low enzymatic activity. However, under opportune stimuli, NEU3 is shifted from the endosomes to the plasma membrane, where it greatly increases the sialidase activity. Finally, we found that NEU3 possesses also the ability to interact with specific proteins, many of which are different in each cell compartment. They were identified by mass spectrometry, and some selected ones were also confirmed by cross-immunoprecipitation with the enzyme, supporting NEU3 involvement in the cell stress response, protein folding, and intracellular trafficking.


Assuntos
Neuraminidase/metabolismo , Membrana Celular/enzimologia , Chaperona BiP do Retículo Endoplasmático , Endossomos/enzimologia , Células HEK293 , Células HeLa , Proteínas de Choque Térmico/metabolismo , Humanos , Neuraminidase/química , Neuraminidase/genética , Dobramento de Proteína , Transporte Proteico , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Estresse Fisiológico , Regulação para Cima
6.
Chemistry ; 21(41): 14614-29, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26397189

RESUMO

Previous studies demonstrated that reducing the GM3 content in myoblasts increased the cell resistance to hypoxic stress, suggesting that a pharmacological inhibition of the GM3 synthesis could be instrumental for the development of new treatments for ischemic diseases. Herein, the synthesis of several dephosphonated CMP-Neu5Ac congeners and their anti-GM3-synthase activity is reported. Biological activity testes revealed that some inhibitors almost completely blocked the GM3-synthase activity in vitro and reduced the GM3 content in living embryonic kidney 293A cells, eventually activating the epidermal growth factor receptor (EGFR) signaling cascade.


Assuntos
Ácido N-Acetilneuramínico do Monofosfato de Citidina/química , Monofosfato de Citidina/análogos & derivados , Inibidores Enzimáticos/química , Inibidores Enzimáticos/síntese química , Receptores ErbB/química , Rim/enzimologia , Ácidos Siálicos/química , Ácidos Siálicos/síntese química , Sialiltransferases/antagonistas & inibidores , Sialiltransferases/química , Monofosfato de Citidina/síntese química , Monofosfato de Citidina/química , Ácido N-Acetilneuramínico do Monofosfato de Citidina/metabolismo , Humanos , Rim/química , Sialiltransferases/metabolismo , Transdução de Sinais/efeitos dos fármacos
7.
Biomed Res Int ; 2015: 402642, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26417594

RESUMO

BACKGROUND: S100B protein, previously proposed as a consolidated marker of brain damage in congenital heart disease (CHD) newborns who underwent cardiac surgery and cardiopulmonary bypass (CPB), has been progressively abandoned due to S100B CNS extra-source such as adipose tissue. The present study investigated CHD newborns, if adipose tissue contributes significantly to S100B serum levels. METHODS: We conducted a prospective study in 26 CHD infants, without preexisting neurological disorders, who underwent cardiac surgery and CPB in whom blood samples for S100B and adiponectin (ADN) measurement were drawn at five perioperative time-points. RESULTS: S100B showed a significant increase from hospital admission up to 24 h after procedure reaching its maximum peak (P < 0.01) during CPB and at the end of the surgical procedure. Moreover, ADN showed a flat pattern and no significant differences (P > 0.05) have been found all along perioperative monitoring. ADN/S100B ratio pattern was identical to S100B alone with the higher peak at the end of CPB and remained higher up to 24 h from surgery. CONCLUSIONS: The present study provides evidence that, in CHD infants, S100B protein is not affected by an extra-source adipose tissue release as suggested by no changes in circulating ADN concentrations.


Assuntos
Adiponectina/sangue , Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ponte Cardiopulmonar/efeitos adversos , Subunidade beta da Proteína Ligante de Cálcio S100/sangue , Pré-Escolar , Feminino , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos
8.
Int J Food Sci Nutr ; 66(6): 603-10, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26306466

RESUMO

The role of inflammation and oxidative stress in atherosclerosis development has been increasingly well recognized over the past decade. Inflammation has a significant role at all stages of atherosclerosis, including initiation, progression and plaque formation. Resveratrol is a naturally occurring polyphenolic compound found in grape products, berry fruits and red wine. Its ability to behave therapeutically as a component of red wine has attracted wide attention. Accumulating evidence suggests that it is a highly pleiotropic molecule that modulates numerous targets and molecular functions. Epidemiological studies indicate that the Mediterranean diet, rich in resveratrol, is associated with a reduced risk of atherosclerosis. Resveratrol is believed to decrease circulating low-density lipoprotein cholesterol levels, reduce cardiovascular disease risk; it reduces lipid peroxidation, platelet aggregation and oxidative stress. Resveratrol is considered a safe compound, since no significant toxic effects have been demonstrated after administration of a broad range of concentrations, and an effective anti-atherogenic agent.


Assuntos
Anti-Inflamatórios não Esteroides/uso terapêutico , Arteriosclerose/tratamento farmacológico , Estilbenos/uso terapêutico , Humanos , Resveratrol
9.
CNS Neurol Disord Drug Targets ; 14(1): 85-90, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25957579

RESUMO

S100B protein has been recently proposed as a consolidated marker of brain damage and death in adult, children and newborn patients. The present study evaluates whether the longitudinal measurement of S100B at different perioperative time-points may be a useful tool to identify the occurrence of perioperative early death in congenital heart disease (CHD) newborns. We conducted a case-control study in 88 CHD infants, without pre-existing neurological disorders or other co-morbidities, of whom 22 were complicated by perioperative death in the first week from surgery. Control group was composed by 66 uncomplicated CHD infants matched for age at surgical procedure. Blood samples were drawn at five predetermined timepoints before during and after surgery. In all CHD children, S100B levels showed a pattern characterized by a significant increase in protein's concentration from hospital admission up to 24-h after procedure reaching their maximum peak (P<0.01) during cardiopulmonary by-pass and at the end of the surgical procedure. Moreover, S100B concentrations in CHD death group were significantly higher (P<0.01) than controls at all monitoring time-points. The ROC curve analysis showed that S100B measured before surgical procedure was the best predictor of perioperative death, among a series of clinical and laboratory parameters, reaching at a cut-off of 0.1 µg/L a sensitivity of 100% and a specificity of 63.7%. The present data suggest that in CHD infants biochemical monitoring in the perioperative period is becoming possible and S100B can be included among a series of parameters for adverse outcome prediction.


Assuntos
Procedimentos Cirúrgicos Cardíacos/efeitos adversos , Ponte Cardiopulmonar/efeitos adversos , Cardiopatias Congênitas , Doenças do Sistema Nervoso/etiologia , Complicações Pós-Operatórias/mortalidade , Proteínas S100/sangue , Resultado do Tratamento , Estudos de Casos e Controles , Feminino , Cardiopatias Congênitas/sangue , Cardiopatias Congênitas/mortalidade , Cardiopatias Congênitas/cirurgia , Humanos , Lactente , Estudos Longitudinais , Masculino , Complicações Pós-Operatórias/epidemiologia , Análise de Regressão , Estatísticas não Paramétricas
10.
CNS Neurol Disord Drug Targets ; 14(1): 12-23, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25613500

RESUMO

Perinatal asphyxia (PA) still constitutes a common complication involving a large number of infants with or without congenital heart diseases (CHD). PA affects 0.2-0.6% of full-term neonates, 20% of which suffer mortal hypoxic-ischemic encephalopathy, and among survivors 25% exhibit permanent consequences at neuropsychological level. Each year, about one third of 1000 live births underwent to surgical intervention in early infancy and/or are at risk for ominous outcome. Advances in brain monitoring, in anesthetic and cardiothoracic surgical techniques, including selective or total body cooling, cardiopulmonary bypass (CPB) and deep hypothermic circulatory arrest, have essentially reduced mortality expanding the possibility to address functional neurologic and cardiac outcomes in long-term survivors. However, open-heart surgery constitutes a time-frame of planned ischemia-reperfusion injury, which is a price to pay in the treatment or palliation of CHD. Infants who underwent heart surgery and non-CHD infants complicated by PA share similarities in their neurodevelopmental profile and a common form of brain damage due to hypoxic-ischemic injury. The purpose of the present review was to evaluate different mechanisms implicated in brain injury following CPB and PA and how it is possible to monitor such injury by means of available biomarkers (S100B protein, Activin A, Adrenomedullin).


Assuntos
Biomarcadores/metabolismo , Lesões Encefálicas , Cardiopatias Congênitas/complicações , Lesões Encefálicas/diagnóstico , Lesões Encefálicas/etiologia , Lesões Encefálicas/metabolismo , Criança , Humanos
11.
BMC Cancer ; 14: 560, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25085576

RESUMO

BACKGROUND: In addition to alterations concerning the expression of oncogenes and onco-suppressors, melanoma is characterized by the presence of distinctive gangliosides (sialic acid carrying glycosphingolipids). Gangliosides strongly control cell surface dynamics and signaling; therefore, it could be assumed that these alterations are linked to modifications of cell behavior acquired by the tumor. On these bases, this work investigated the correlations between melanoma cell ganglioside metabolism profiles and the biological features of the tumor and the survival of patients. METHODS: Melanoma cell lines were established from surgical specimens of AJCC stage III and IV melanoma patients. Sphingolipid analysis was carried out on melanoma cell lines and melanocytes through cell metabolic labeling employing [3-3H]sphingosine and by FACS. N-glycolyl GM3 was identified employing the 14 F7 antibody. Gene expression was assayed by Real Time PCR. Cell invasiveness was assayed through a Matrigel invasion assay; cell proliferation was determined through the soft agar assay, MTT, and [3H] thymidine incorporation. Statistical analysis was performed using XLSTAT software for melanoma hierarchical clustering based on ganglioside profile, the Kaplan-Meier method, the log-rank (Mantel-Cox) test, and the Mantel-Haenszel test for survival analysis. RESULTS: Based on the ganglioside profiles, through a hierarchical clustering, we classified melanoma cells isolated from patients into three clusters: 1) cluster 1, characterized by high content of GM3, mainly in the form of N-glycolyl GM3, and GD3; 2) cluster 2, characterized by the appearance of complex gangliosides and by a low content of GM3; 3) cluster 3, which showed an intermediate phenotype between cluster 1 and cluster 3. Moreover, our data demonstrated that: a) a correlation could be traced between patients' survival and clusters based on ganglioside profiles, with cluster 1 showing the worst survival; b) the expression of several enzymes (sialidase NEU3, GM2 and GM1 synthases) involved in ganglioside metabolism was associated with patients' survival; c) melanoma clusters showed different malignant features such as growth in soft agar, invasiveness, expression of anti-apoptotic proteins. CONCLUSIONS: Ganglioside profile and metabolism is strictly interconnected with melanoma aggressiveness. Therefore, the profiling of melanoma gangliosides and enzymes involved in their metabolism could represent a useful prognostic and diagnostic tool.


Assuntos
Gangliosídeos/metabolismo , Melanoma/patologia , Análise por Conglomerados , Regulação Neoplásica da Expressão Gênica , Glicosiltransferases/metabolismo , Humanos , Melanoma/metabolismo , Metástase Neoplásica , Prognóstico , Análise de Sobrevida , Células Tumorais Cultivadas
12.
J Lipid Res ; 55(3): 549-60, 2014 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-24449473

RESUMO

Owing to their exposure on the cell surface and the possibility of being directly recognized with specific antibodies, glycosphingolipids have aroused great interest in the field of stem cell biology. In the search for specific markers of the differentiation of human bone marrow mesenchymal stem cells (hBMSCs) toward osteoblasts, we studied their glycosphingolipid pattern, with particular attention to gangliosides. After lipid extraction and fractionation, gangliosides, metabolically (3)H-labeled in the sphingosine moiety, were separated by high-performance TLC and chemically characterized by MALDI MS. Upon induction of osteogenic differentiation, a 3-fold increase of ganglioside GD1a was observed. Therefore, the hypothesis of GD1a involvement in hBMSCs commitment toward the osteogenic phenotype was tested by comparison of the osteogenic propensity of GD1a-highly expressing versus GD1a-low expressing hBMSCs and direct addition of GD1a in the differentiation medium. It was found that either the high expression of GD1a in hBMSCs or the addition of GD1a in the differentiation medium favored osteogenesis, providing a remarkable increase of alkaline phosphatase. It was also observed that ganglioside GD2, although detectable in hBMSCs by immunohistochemistry with an anti-GD2 antibody, could not be recognized by chemical analysis, likely reflecting a case, not uncommon, of molecular mimicry.


Assuntos
Biomarcadores/metabolismo , Diferenciação Celular , Gangliosídeos/metabolismo , Células-Tronco/metabolismo , Fosfatase Alcalina/genética , Células da Medula Óssea/citologia , Células da Medula Óssea/metabolismo , Células Cultivadas , Subunidade alfa 1 de Fator de Ligação ao Core/genética , Derme/citologia , Relação Dose-Resposta a Droga , Fibroblastos/citologia , Fibroblastos/metabolismo , Citometria de Fluxo , Gangliosídeos/farmacologia , Expressão Gênica/efeitos dos fármacos , Humanos , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/metabolismo , Osteoblastos/citologia , Osteoblastos/metabolismo , Osteogênese/efeitos dos fármacos , Osteogênese/genética , Osteopontina/genética , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Esfingolipídeos/metabolismo , Células-Tronco/citologia
13.
Electrophoresis ; 35(9): 1319-28, 2014 May.
Artigo em Inglês | MEDLINE | ID: mdl-24375639

RESUMO

Glycosphingolipids (GSLs) are a class of ubiquitous lipids characterized by a wide structural repertoire and a variety of functional implications. Importantly, altered levels have been correlated with different diseases, suggesting their crucial role in health. Conventional methods for the characterization and quantification are based on high-performance TLC (HPTLC) separation and comparison with the migration distance of standard samples or on MS. We set up and herein report the application of an ImagePrep method for glycosphingolipids qualitative and quantitative profiling through direct HPTLC-MALDI with particular application to wild-type and NEU3 sialidase-overexpressing C2C12 myoblasts. Lipids were analyzed by HPTLC, coupled with MALDI-TOF, and the resulting GSLs profiles were compared to the [³H]sphingolipids HPTLC patterns obtained after metabolic radiolabeling. GSLs detection by HPTLC-MALDI was optimized by testing different methods for matrix delivery and by performing quantitative analyses using serial dilutions of GSLs standards. Through this approach an accurate analysis of each variant of neutral and acidic GSLs, including the detection of different fatty-acid chain variants for each GSL, was provided and these results demonstrated that HPTLC-MALDI is an easy and high-throughput analytical method for GSLs profiling, suggesting its use for an early detection of markers in different diseases, including cancer and heart ischemia.


Assuntos
Glicoesfingolipídeos Acídicos/análise , Cromatografia Líquida de Alta Pressão/métodos , Cromatografia em Camada Fina/métodos , Neuraminidase/metabolismo , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz/métodos , Glicoesfingolipídeos Acídicos/metabolismo , Animais , Área Sob a Curva , Linhagem Celular , Modelos Lineares , Camundongos , Mioblastos
14.
Food Funct ; 4(8): 1195-203, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23681196

RESUMO

Intestinal cells are continuously exposed to food whose components are able to modulate some of their physiological functions. Among the bioactive food derivatives are casein phosphopeptides (CPPs), coming from the in vitro or in vivo casein digestion, which display the ability to form aggregates with calcium ions and to increase the uptake of the minerals in differentiated intestinal human HT-29 and Caco2 cells. Since extracellular calcium is a known inactivator of the TRPV6 channel, which is also involved in the colon cancer progression, the present study aims to determine a possible modulation by CPPs of the molecular structures responsible for paracellular and/or transcellular calcium absorption in these two cell lines. The paracellular calcium transport was determined by TEER measurements in Caco2 cells and by Lucifer Yellow flow in HT-29 cells. The possible modulation of transcellular calcium absorption machinery by CPPs was investigated by determining the mRNA expression for both the TRPV6 calcium channel and the VDR receptor in 1,25(OH)2D3 pre-treated undifferentiated/differentiated cells. The results obtained point out that: (i) CPPs do not affect paracellular calcium absorption; (ii) 1,25(OH)2D3 increases the TRPV6 mRNA expression in both types of cells. In the case of HT-29 cells this is the first determination of the presence of the TRPV6 channel; (iii) CPPs per se are not able to affect the VDR and TRPV6 mRNA expression; (iv) CPP administration does not affect the TRPV6 mRNA expression in 1,25(OH)2D3 pre-treated HT-29 cells and Caco2 cells. Unlike peptides coming from the digestion of cheese whey protein digest, the digestion of milk casein produces peptides with no effects on TRPV6 calcium channel expression, though the same peptides are able to determine a calcium uptake by the intestinal cells.


Assuntos
Cálcio/metabolismo , Caseínas/metabolismo , Mucosa Intestinal/metabolismo , Fosfopeptídeos/metabolismo , Vitamina D/metabolismo , Células CACO-2 , Células HT29 , Humanos , Canais de Cátion TRPV/genética , Canais de Cátion TRPV/metabolismo , Transcitose
15.
J Biol Chem ; 288(5): 3153-62, 2013 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-23209287

RESUMO

NEU3 sialidase, a key enzyme in ganglioside metabolism, is activated under hypoxic conditions in cultured skeletal muscle cells (C2C12). NEU3 up-regulation stimulates the EGF receptor signaling pathway, which in turn activates the hypoxia-inducible factor (HIF-1α), resulting in a final increase of cell survival and proliferation. In the same cells, stable overexpression of sialidase NEU3 significantly enhances cell resistance to hypoxia, whereas stable silencing of the enzyme renders cells more susceptible to apoptosis. These data support the working hypothesis of a physiological role played by NEU3 sialidase in protecting cells from hypoxic stress and may suggest new directions in the development of therapeutic strategies against ischemic diseases, particularly of the cerebro-cardiovascular system.


Assuntos
Apoptose , Receptores ErbB/metabolismo , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Células Musculares/citologia , Células Musculares/enzimologia , Músculo Esquelético/citologia , Neuraminidase/metabolismo , Animais , Western Blotting , Caspases/metabolismo , Hipóxia Celular , Linhagem Celular , Proliferação de Células , Citoproteção , Ativação Enzimática , Gangliosídeo G(M3)/metabolismo , Inativação Gênica , Camundongos , Modelos Biológicos , Sialiltransferases/metabolismo , Transdução de Sinais , Fator de Transcrição Sp1/genética , Fator de Transcrição Sp1/metabolismo , Fator de Transcrição Sp3/genética , Fator de Transcrição Sp3/metabolismo , Esfingolipídeos/metabolismo , Regulação para Cima/genética
16.
J Biol Chem ; 287(51): 42835-45, 2012 Dec 14.
Artigo em Inglês | MEDLINE | ID: mdl-23139422

RESUMO

The human plasma membrane sialidase NEU3 is a key enzyme in the catabolism of membrane gangliosides, is crucial in the regulation of cell surface processes, and has been demonstrated to be significantly up-regulated in renal cell carcinomas (RCCs). In this report, we show that NEU3 regulates ß1 integrin trafficking in RCC cells by controlling ß1 integrin recycling to the plasma membrane and controlling activation of the epidermal growth factor receptor (EGFR) and focal adhesion kinase (FAK)/protein kinase B (AKT) signaling. NEU3 silencing in RCC cells increased the membrane ganglioside content, in particular the GD1a content, and changed the expression of key regulators of the integrin recycling pathway. In addition, NEU3 silencing up-regulated the Ras-related protein RAB25, which directs internalized integrins to lysosomes, and down-regulated the chloride intracellular channel protein 3 (CLIC3), which induces the recycling of internalized integrins to the plasma membrane. In this manner, NEU3 silencing enhanced the caveolar endocytosis of ß1 integrin, blocked its recycling and reduced its levels at the plasma membrane, and, consequently, inhibited EGFR and FAK/AKT. These events had the following effects on the behavior of RCC cells: they (a) decreased drug resistance mediated by the block of autophagy and the induction of apoptosis; (b) decreased metastatic potential mediated by down-regulation of the metalloproteinases MMP1 and MMP7; and (c) decreased adhesion to collagen and fibronectin. Therefore, our data identify NEU3 as a key regulator of the ß1 integrin-recycling pathway and FAK/AKT signaling and demonstrate its crucial role in RCC malignancy.


Assuntos
Carcinoma de Células Renais/patologia , Membrana Celular/enzimologia , Endocitose , Integrina beta1/metabolismo , Neoplasias Renais/patologia , Neuraminidase/metabolismo , Carcinoma de Células Renais/enzimologia , Carcinoma de Células Renais/genética , Adesão Celular , Diferenciação Celular/genética , Linhagem Celular Tumoral , Regulação para Baixo , Resistencia a Medicamentos Antineoplásicos , Endocitose/genética , Receptores ErbB/metabolismo , Quinase 1 de Adesão Focal/metabolismo , Regulação Neoplásica da Expressão Gênica , Inativação Gênica , Glicoesfingolipídeos/metabolismo , Humanos , Neoplasias Renais/enzimologia , Neoplasias Renais/genética , Metaloproteinase 1 da Matriz/genética , Metaloproteinase 1 da Matriz/metabolismo , Metaloproteinase 7 da Matriz/genética , Metaloproteinase 7 da Matriz/metabolismo , Invasividade Neoplásica , Transporte Proteico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Transdução de Sinais
17.
Skelet Muscle ; 2(1): 23, 2012 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-23114189

RESUMO

The family of mammalian sialidases is composed of four distinct versatile enzymes that remove negatively charged terminal sialic acid residues from gangliosides and glycoproteins in different subcellular areas and organelles, including lysosomes, cytosol, plasma membrane and mitochondria. In this review we summarize the growing body of data describing the important role of sialidases in skeletal muscle, a complex apparatus involved in numerous key functions and whose functional integrity can be affected by various conditions, such as aging, chronic diseases, cancer and neuromuscular disorders. In addition to supporting the proper catabolism of glycoconjugates, sialidases can affect different signaling pathways by desialylation of many receptors and modulation of ganglioside content in cell membranes, thus actively participating in myoblast proliferation, differentiation and hypertrophy, insulin responsiveness and skeletal muscle architecture.

18.
J Cell Biochem ; 113(10): 3207-17, 2012 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-22615034

RESUMO

The synthetic purine reversine has been shown to possess a dual activity as it promotes the de-differentiation of adult cells, including fibroblasts, into stem-cell-like progenitors, but it also induces cell growth arrest and ultimately cell death of cancer cells, suggesting its possible application as an anti-cancer agent. Aim of this study was to investigate the mechanism underneath reversine selectivity in inducing cell death of cancer cells by a comparative analysis of its effects on several tumor cells and normal dermal fibroblasts. We found that reversine is lethal for all cancer cells studied as it induces cell endoreplication, a process that malignant cells cannot effectively oppose due to aberrations in cell cycle checkpoints. On the other hand, normal cells, like dermal fibroblasts, can control reversine activity by blocking the cell cycle, entering a reversible quiescent state. However, they can be induced to become sensitive to the molecule when key cell cycle proteins, e.g., p53, are silenced.


Assuntos
Antineoplásicos/farmacologia , Morfolinas/farmacologia , Purinas/farmacologia , Proteína Supressora de Tumor p53/metabolismo , Benzotiazóis/farmacologia , Western Blotting , Caspases/metabolismo , Pontos de Checagem do Ciclo Celular , Morte Celular , Desdiferenciação Celular , Proliferação de Células , Forma Celular/efeitos dos fármacos , Sobrevivência Celular , Endorreduplicação , Ativação Enzimática , Fibroblastos/efeitos dos fármacos , Fibrossarcoma/genética , Fibrossarcoma/metabolismo , Fibrossarcoma/patologia , Citometria de Fluxo , Inativação Gênica , Células HeLa , Humanos , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Tolueno/análogos & derivados , Tolueno/farmacologia , Proteína Supressora de Tumor p53/antagonistas & inibidores , Proteína Supressora de Tumor p53/genética
19.
Int J Cancer ; 131(8): 1768-78, 2012 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-22287118

RESUMO

Neuroblastoma (NB) is a frequently lethal tumor that occurs in childhood and originates from embryonic neural crest cells. The malignant and aggressive phenotype of NB is strictly related to the deregulation of pivotal pathways governing the proliferation/differentiation status of neural crest precursor cells, such as MYCN, Delta/Notch and Wnt/ß-catenin (CTNNB1) signaling. In this article, we demonstrate that sialidase NEU4 long (NEU4L) influences the differentiation/proliferation behavior of NB SK-N-BE cells by determining hyperactivation of the Wnt/ß-catenin signaling pathway. NEU4L overexpression in SK-N-BE cells induced significant increases in active, nonphosphorylated ß-catenin content, ß-catenin/TCF transcriptional activity and ß-catenin gene target expression including MYCN, MYC, CCND2 (cyclin D2) and CDC25A. In turn, these molecular features strongly modified the behavior of NEU4L SK-N-BE overexpressing cells, promoting the following: (1) an enhanced proliferation rate, mainly due to a faster transition from G1 to S phase in the cell cycle; (2) a more undifferentiated cell phenotype, which was similar to stem-like NB cells and possibly mediated by an increase of the expression of the pluripotency genes, MYC, NANOG, OCT-4, CD133 and NES (nestin); (3) the failure of NB cell differentiation after serum withdrawal. The molecular link between NEU4L and Wnt/ß-catenin signaling appeared to rely most likely on the capability of the enzyme to modify the sialylation level of cell glycoproteins. These findings could provide a new candidate for therapeutic treatment.


Assuntos
Diferenciação Celular , Proliferação de Células , Neuraminidase/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/patologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Western Blotting , Comunicação Celular , Ciclo Celular , Meios de Cultura Livres de Soro/farmacologia , Glicoproteínas/metabolismo , Humanos , Potencial da Membrana Mitocondrial , Transdução de Sinais , Células-Tronco/efeitos dos fármacos , Células Tumorais Cultivadas , Via de Sinalização Wnt
20.
J Nutr Biochem ; 23(7): 808-16, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-21840696

RESUMO

At the intestinal level, proliferation and apoptosis are modulated by the extracellular calcium concentration; thus, dietary calcium may exert a chemoprotective role on normal differentiated intestinal cells, while it may behave as a carcinogenesis promoter in transformed cells. Calcium in milk is associated with casein and casein phosphopeptides (CPPs), hence is preserved from precipitation. CPPs were demonstrated to induce uptake of extracellular calcium ions by in vitro intestinal tumor HT-29 cells but only upon differentiation. Here, the hypothesis that CPPs could differently affect proliferation and apoptosis in undifferentiated and differentiated HT-29 cells through their binding with calcium ions was investigated. Results showed that CPPs protect differentiated intestinal cells from calcium overload toxicity and prevent their apoptosis favoring proliferation while inducing apoptosis in undifferentiated tumor cells. The CPP effect on undifferentiated HT-29 cells, similar to that exerted by ethyleneglycol-O, O'-bis(2-aminoethyl)-N, N, N', N'-tetraacetic acid (EGTA), is presumably due to the ability in binding the extracellular calcium. The effect on differentiated HT-29 cells is coupled to the interaction of CPPs with the voltage-operated L-type calcium channels, known to activate calcium entry into the cells under depolarization and to exert a mitogenic effect: the use of an agonist potentiates the cell response to CPPs, while the antagonists abolish the response to CPPs (36% of examined cells) or reduce both the percentage of responsive cells and the increase of intracellular calcium concentration. Taken together, these results confirm the potentialities of CPPs as nutraceuticals/functional food and also as modulators of cellular processes connected to the expression of a cancer phenotype.


Assuntos
Apoptose/efeitos dos fármacos , Canais de Cálcio Tipo L/metabolismo , Caseínas/metabolismo , Proliferação de Células/efeitos dos fármacos , Fosfopeptídeos/metabolismo , Diferenciação Celular , Suplementos Nutricionais , Ácido Egtázico/metabolismo , Células HT29 , Humanos
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