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1.
Eur J Public Health ; 29(5): 943-947, 2019 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-31219550

RESUMO

BACKGROUND: The Italian National Institute of Health (Istituto Superiore di Sanità, ISS) considers health inequalities (HI) an important area of activity. As the scientific and technical body of the Ministry of Health and the National Health Service, ISS may play a key role to reduce HI. In order to enable ISS in addressing the new and crucial HI challenge, a Research Positioning Exercise was designed and implemented. METHODS: The Exercise included: (i) workshop to strengthen the institutional interest in the field of HI; (ii) review and analysis of ISS publications (years 2000-2017) to identify HI research topics; (iii) survey among ISS researchers regarding main research challenges to address HI in the coming years; and (iv) analysis of input on research challenges from HI international experts. RESULTS: The results of this Exercise suggest that the following points should be included in the future ISS agenda planning: (i) themes which ISS should continue working on (e.g. migrants/vulnerable groups); (ii) themes to be improved: (a) relationship between social determinants and mechanism of HI generation and (b) relationship between risk factors exposure and social determinants; and (iii) new themes to be addressed: (a) mechanisms underlying the resilience observed in Italy; (b) new socioeconomic indicators for HI monitoring; and (c) evidence-based policies aimed at reducing HI. CONCLUSION: Findings of this Exercise show that ISS researchers identified relevant areas, addressing inequalities in addressing the health. Because of ISS structural peculiarity that includes multidisciplinary expertise, the ISS could provide a significant contribution to HI research challenges and knowledge gaps.


Assuntos
Pesquisa Biomédica , Educação , Disparidades nos Níveis de Saúde , Proteínas de Arabidopsis , Pesquisa Biomédica/organização & administração , Órgãos Governamentais/organização & administração , Histona-Lisina N-Metiltransferase , Humanos , Itália/epidemiologia , Pesquisa , Fatores de Risco , Determinantes Sociais da Saúde , Populações Vulneráveis
2.
J Pathol ; 229(2): 208-20, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23018629

RESUMO

Fibrotic disorders are multistage progressive processes that often arise from different causes and are commonly associated with chronic inflammation. Excessive deposition of extracellular matrix is the hallmark of many fibrotic diseases. This may be due to an excess of fibroblast recruitment and activation, as well as to their differentiation in myofibroblasts. These events may be triggered by cytokines, chemokines and growth factors released by lymphocytes or macrophages. The excessive production of extracellular matrix is apparently due to alterations of metabolic pathways in activated fibroblasts. It has been suggested that a defective autophagy, an important subcellular pathway with multiple homeostatic roles, also recognized as a key component of both innate and acquired immunity, could play a role. In this review we illustrate recent insights in the field, suggesting the possible implication of the immune system in orchestrating the fibrotic response via the modulation of autophagic pathways.


Assuntos
Autofagia , Fibroblastos/patologia , Animais , Matriz Extracelular/metabolismo , Matriz Extracelular/patologia , Fibroblastos/imunologia , Fibroblastos/metabolismo , Fibrose , Homeostase , Humanos , Transdução de Sinais
3.
Arch Public Health ; 81(1): 89, 2023 May 11.
Artigo em Inglês | MEDLINE | ID: mdl-37170153

RESUMO

Health inequalities within and between Member States of the European Union are widely recognized as a public health problem as they determine a significant share of potentially avoidable mortality and morbidity. After years of growing awareness and increasing action taken, a large gap still exists across Europe in terms of policy responses and governance. With the aim to contribute to achieve greater equity in health outcomes, in 2018 a new Joint Action, JAHEE, (Joint Action Health Equity Europe) was funded by the third EU Health Programme, with the main goal of strengthening cooperation between participating countries and of implementing concrete actions to reduce health inequalities. The partnership led by Italy counted 24 countries, conducting actions in five policy domains: monitoring, governance, healthy living environments, health systems and migration, following a three-step implementation approach. Firstly, specific Policy Frameworks for Action (PFA) collecting the available evidence on what practice should be done in each domain were developed. Second, different Country Assessments (CAs) were completed to check the country's adherence to the recommended practice in each domain. The gap between the expected policy response (PFA) and the present policy response (CA) guided the choice of concrete actions to be implemented in JAHEE, many of which are continuing even after the end of JA. Final recommendations based on the best results achieved during JAHEE were elaborated and agreed jointly with the representatives of the involved Ministries of Health. The JAHEE initiative represented an important opportunity for the participating countries to work jointly, and the results show that almost all have increased their level of action and strengthened their capacities to address health inequalities.

4.
Int J Cancer ; 131(4): E337-47, 2012 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-21913183

RESUMO

2-Deoxy-D-glucose (2DG) is a synthetic glucose analogue that inhibits glycolysis and blocks cancer cell growth. In this report, we evaluated the role of 2DG in the induction of cell death in human metastatic melanoma cells. We have also examined the effects of 2DG in combined treatments with four different pro-apoptotic agents: (i) Temozolomide (TMZ), a chemotherapic drug commonly used to treat metastatic melanoma, (ii) Pyrimethamine (Pyr), a pro-apoptotic antifolate drug recently reappraised in cancer therapy, (iii) Cisplatin (CisPt), a drug capable of directly binding to DNA ultimately triggering apoptosis of cancer cells and (iv) the kinase inhibitor Staurosporine (STS), a prototypical inducer of mitochondria-mediated apoptosis. We found that 2DG per se: (i) induced a cell cycle arrest in G(0) /G(1) , (ii) promoted autophagy, (iii) was ineffective in inducing apoptosis in association with the chemotherapic drug TMZ, whereas (iv) it was synergistic with CisPt and STS pro-apoptotic drugs through a mechanism involving changes of mitochondrial homeostasis. Conversely, (v) 2DG hindered the pro-apoptotic effects of Pyr via a mechanism involving either the block of cell cycle in G(0) /G(1) or the modification of the free radical production of the cell, i.e., decreasing the production of reactive oxygen species (ROS) and increasing the production of reactive nitrogen species (RNS). Moreover, a clear-cut autophagic response involving endoplasmic reticulum remodelling was detectable. Since autophagic cytoprotection has been suggested to contribute to the induction of chemoresistance, these results could provide useful clues as concerns the use of 2DG as anticancer agent in combinatory protocols.


Assuntos
Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Autofagia/efeitos dos fármacos , Desoxiglucose/farmacologia , Glicólise/efeitos dos fármacos , Melanoma/patologia , Metástase Neoplásica , Trifosfato de Adenosina/biossíntese , Proteínas Reguladoras de Apoptose/metabolismo , Proteína Beclina-1 , Ciclo Celular , Linhagem Celular Tumoral , Humanos , Melanoma/imunologia , Melanoma/metabolismo , Proteínas de Membrana/metabolismo , Microscopia Eletrônica de Transmissão , Mitocôndrias/metabolismo , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Espécies Reativas de Nitrogênio/metabolismo , Espécies Reativas de Oxigênio/metabolismo
5.
Cell Physiol Biochem ; 30(2): 418-27, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22814239

RESUMO

AIMS: The aim of this work was to investigate whether systemic oxidative imbalance that occurs in patients with systemic sclerosis affects red blood cell integrity. METHODS: Reactive oxygen species, intracellular content of total thiols and molecules involved in red blood cell aging (e.g., glycophorin A, band 3, CD47 and phosphatidylserine externalization), have been analyzed in erythrocytes from 39 patients with systemic sclerosis and 30 healthy donors by using flow and static cytometry. Analyses were carried out taking into account the two clinical subsets of scleroderma: diffuse cutaneous sclerosis and limited cutaneous sclerosis. RESULTS: A significant reduction (p<0.05) of intracellular total thiols and a significant loss (p<0.01) of glycophorin A, band 3 and CD47 was found in red blood cells from patients with limited cutaneous sclerosis. Conversely, a significant increase (p<0.01) of reactive oxygen species levels and CD47 expression was found in red blood cells from patients with diffuse cutaneous sclerosis. Phosphatidylserine externalization was significantly increased both in patients with limited and diffuse disease. Importantly, this increase was related with disease severity and nailfold capillaroscopy. CONCLUSIONS: Altogether these results suggest a reappraisal of the red blood cells as useful markers in the clinical management of the disease.


Assuntos
Eritrócitos/metabolismo , Escleroderma Sistêmico/fisiopatologia , Adulto , Idoso , Proteína 1 de Troca de Ânion do Eritrócito/metabolismo , Antígeno CD47/metabolismo , Senescência Celular/efeitos dos fármacos , Eritrócitos/efeitos dos fármacos , Feminino , Citometria de Fluxo , Glicoforinas/metabolismo , Humanos , Masculino , Angioscopia Microscópica , Pessoa de Meia-Idade , Fosfatidilserinas/farmacologia , Projetos Piloto , Espécies Reativas de Oxigênio/metabolismo , Escleroderma Sistêmico/metabolismo , Compostos de Sulfidrila/metabolismo
6.
Clin Immunol ; 137(1): 122-33, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20580318

RESUMO

We investigated in systemic sclerosis (SSc) patients the T cell homeostasis and its relationship with the clinical course of the disease. Distribution of peripheral T cell subsets, thymic output, lymphocyte proliferation and apoptosis were analyzed by flow cytometry or ELISA. Age inappropriate levels of naive CD4(+) T cells and thymic output were observed. Proliferation of CD4(+) T cells, lymphocyte apoptosis and CD4(+) regulatory T (Treg) cell frequency were significantly higher than those observed in controls and significantly correlated with clinical phenotypes and clinical progression parameters i.e., diffusing capacity of the lung for carbon monoxide (DLCO) and disease activity. These data indicate that the evaluation of the T cell homeostasis can represent a valuable prognostic tool for SSc patients and it is useful to distinguish between limited and diffuse phenotypes. A therapeutic intervention targeted at reversing T cell homeostasis abnormalities would therefore potentially be helpful in counteracting disease progression.


Assuntos
Homeostase/imunologia , Escleroderma Sistêmico/imunologia , Escleroderma Sistêmico/fisiopatologia , Linfócitos T/imunologia , Linfócitos T/patologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/imunologia , Apoptose/imunologia , Contagem de Linfócito CD4 , Monóxido de Carbono/metabolismo , Proliferação de Células , Feminino , Humanos , Imunofenotipagem , Masculino , Pessoa de Meia-Idade , Molécula-1 de Adesão Celular Endotelial a Plaquetas/metabolismo , Troca Gasosa Pulmonar/fisiologia , Esclerodermia Difusa/sangue , Esclerodermia Difusa/diagnóstico , Esclerodermia Difusa/imunologia , Esclerodermia Difusa/fisiopatologia , Esclerodermia Limitada/sangue , Esclerodermia Limitada/diagnóstico , Esclerodermia Limitada/imunologia , Esclerodermia Limitada/fisiopatologia , Escleroderma Sistêmico/sangue , Escleroderma Sistêmico/diagnóstico , Índice de Gravidade de Doença , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Subpopulações de Linfócitos T/patologia , Linfócitos T/metabolismo , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/patologia , Adulto Jovem
7.
FASEB J ; 23(10): 3298-308, 2009 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-19509307

RESUMO

In a previous investigation, we demonstrated that after CD95/Fas triggering, raft-associated GD3 ganglioside, normally localized at the plasma membrane of T cells, can be detected in mitochondria, where they contribute to apoptogenic events. Here, we show the association of the glycosphingolipid GD3 with microtubular cytoskeleton at very early time points following Fas ligation. This was assessed by different methodological approaches, including fluorescence resonance energy transfer, immunoelectron microscopy, and coimmunoprecipitation. Furthermore, docking analysis also showed that GD3 has a high affinity for the pore formed by 4 tubulin heterodimers (type I pore), thus suggesting a possible direct interaction between tubulin and GD3. Finally, time-course analyses indicated that the relocalization of GD3 to the mitochondria was time related with the alterations of the mitochondrial membrane potential. Hence, microtubules could act as tracks for ganglioside redistribution following apoptotic stimulation, possibly contributing to the mitochondrial alterations leading to cell death.


Assuntos
Gangliosídeos/metabolismo , Microdomínios da Membrana/metabolismo , Microtúbulos/metabolismo , Tubulina (Proteína)/metabolismo , Receptor fas/metabolismo , Linhagem Celular Tumoral , Simulação por Computador , Gangliosídeos/química , Humanos , Microdomínios da Membrana/química , Mitocôndrias/metabolismo , Modelos Biológicos , Conformação Proteica , Tubulina (Proteína)/química , Receptor fas/química
9.
Int Arch Allergy Immunol ; 145(3): 258-67, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-17921676

RESUMO

BACKGROUND: Evans syndrome (ES) is a rare disorder characterized by combined autoimmune thrombocytopenia and autoimmune hemolytic anemia. Several studies have documented a number of B cell defects, whereas only limited information is currently available about the T cell subset. METHODS: A wide panel of immunological analyses aiming specifically at a quantitative and qualitative evaluation of the T cell compartment was performed in an unusual case of ES. The peripheral distribution of the T cell subsets, the diversity of the T cell receptor (TCR) repertoires, the cytokine profile and the T cell apoptosis have been longitudinally evaluated. RESULTS: On first investigation, flow-cytometric immunophenotyping showed a remarkable alteration of T cell homeostasis with deeply reduced CD4+ naive T cells and recent thymic emigrants. This was seen in association with increased levels of T cell activation and apoptosis. Consistently with these data the cytokine profile was characterized by high interferon-gamma and low interleukin-2 levels. Staining for CD4 and CD25 molecules showed decreased percentages of circulating regulatory T cells according to the autoimmune nature of ES. Finally, restricted TCR repertoires were demonstrated by a skewed TCR beta chain variable (TCRBV) gene usage as well as oligoclonal third complementarity-determining region (CDR3) profiles. A deterioration of the above-mentioned parameters and a worsening of the clinical condition were observed during the follow-up requiring more intensive treatments. CONCLUSION: The demonstration of multiple T cell defects, in addition to providing pathogenetic information, is likely to alter both acute treatment and outcome of ES.


Assuntos
Anemia Hemolítica Autoimune/imunologia , Doenças Autoimunes/imunologia , Subpopulações de Linfócitos T/fisiologia , Trombocitopenia/imunologia , Adolescente , Apoptose , Antígenos CD4/análise , Antígenos CD4/metabolismo , Linfócitos T CD4-Positivos/imunologia , Células Cultivadas , Regiões Determinantes de Complementaridade/análise , Citometria de Fluxo , Humanos , Interferon gama/metabolismo , Interleucina-2/metabolismo , Subunidade alfa de Receptor de Interleucina-2/análise , Subunidade alfa de Receptor de Interleucina-2/metabolismo , Estudos Longitudinais , Ativação Linfocitária , Masculino , Receptores de Antígenos de Linfócitos T alfa-beta/genética , Receptores de Antígenos de Linfócitos T alfa-beta/imunologia , Subpopulações de Linfócitos T/patologia , Subpopulações de Linfócitos T/ultraestrutura , Timo/imunologia
11.
FEBS Lett ; 581(21): 3899-903, 2007 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-17662725

RESUMO

Plasma membrane lipid rafts have been considered as a sort of "chamber", where several subcellular activities, including CD95/Fas-mediated pro-apoptotic signaling, can take place. Recently, we demonstrated that, after CD95/Fas triggering, raft-like microdomains could be detected in mitochondrial membranes. The mitochondrion appears as a dynamic and subcompartmentalized organelle in which microdomains might act as controllers of apoptosis-associated fission that results in the release of apoptogenic factors. Here, we hypothesize that some "small" mitochondria, possibly derived from their fission process, can reach the nuclear envelope and strictly interact with this. Mitochondria could act as a signaling "device" contributing to molecular trafficking of molecules, including raft-like components, during apoptosis.


Assuntos
Apoptose/fisiologia , Núcleo Celular/metabolismo , Gangliosídeos/metabolismo , Microdomínios da Membrana/metabolismo , Mitocôndrias/metabolismo , Membranas Mitocondriais/metabolismo , Transporte Ativo do Núcleo Celular/fisiologia , Animais , Proteína Ligante Fas/metabolismo , Humanos , Transdução de Sinais/fisiologia , Receptor fas/metabolismo
12.
Oncotarget ; 8(69): 113938-113956, 2017 Dec 26.
Artigo em Inglês | MEDLINE | ID: mdl-29371959

RESUMO

Trimetazidine (TMZ) is a metabolic reprogramming agent able to partially inhibit mitochondrial free fatty acid ß-oxidation while enhancing glucose oxidation. Here we have found that the metabolic shift driven by TMZ enhances the myogenic potential of skeletal muscle progenitor cells leading to MyoD, Myogenin, Desmin and the slow isoforms of troponin C and I over-expression. Moreover, similarly to exercise, TMZ stimulates the phosphorylation of the AMP-activated protein kinase (AMPK) and up-regulates the peroxisome proliferator-activated receptor gamma coactivator 1-α (PGC1α), both of which are known to enhance the mitochondrial biogenesis necessary for myoblast differentiation. TMZ also induces autophagy which is required during myoblast differentiation and promotes myoblast alignment which allows cell fusion and myofiber formation. Finally, we found that intraperitoneally administered TMZ (5mg/kg) is able to stimulate myogenesis in vivo both in a mice model of cancer cachexia (C26 mice) and upon cardiotoxin damage. Collectively, our work demonstrates that TMZ enhances myoblast differentiation and promotes myogenesis, which might contribute recovering stem cell blunted regenerative capacity and counteracting muscle wasting, thanks to the formation of new myofibers; TMZ is already in use in humans as an anti-anginal drug and its repositioning might impact significantly on aging and regeneration-impaired disorders, including cancer cachexia, as well as have implications in regenerative medicine.

13.
FEBS Lett ; 580(13): 3335-9, 2006 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-16707128

RESUMO

Critical changes occurring in Rac-1 molecule, a cytoskeleton organizing small GTPase associated with cell ruffling, have been analyzed in dendritic cells (DCs) derived from monocytes cultured with granulocyte-macrophage colony-stimulating factor and IFN-alpha or IL-4. Although with different kinetics, both agents induced activation of Rac-1 molecule and, more importantly, an upregulation of both protein expression and mRNA transcription. These findings strengthen the role of Rac-1 molecule in the induction of DC differentiation and suggest that, besides its activation, the upregulation of Rac-1 molecule might also play a role in the acquisition of DC mature phenotype.


Assuntos
Células Dendríticas/citologia , Monócitos/citologia , Proteínas rac1 de Ligação ao GTP/metabolismo , Diferenciação Celular , Citocinas/farmacologia , Citoesqueleto/ultraestrutura , Células Dendríticas/enzimologia , Ativação Enzimática , Humanos , Monócitos/efeitos dos fármacos , Monócitos/enzimologia , RNA Mensageiro/metabolismo , Transcrição Gênica , Regulação para Cima , Proteínas rac1 de Ligação ao GTP/genética
14.
Ann Ist Super Sanita ; 52(2): 190-7, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27364393

RESUMO

The increasing proportion of women in the workforce raises a range of gender-related questions about the different effects of work-related risks on men and women. Few studies have characterized gender differences across occupations and industries, although at this time, the gender sensitive approach is starting to acquire relevance in the field of human preventive medicine. The European Agency for Safety and Health at Work has encouraged a policy of gender equality in all European member states. Italy has adopted European provisions with new specific legislation that integrates the previous laws and introduces the gender differences into the workplace. Despite the fact that gender equal legislation opportunities have been enacted in Italy, their application is delayed by some difficulties. This review examines some of these critical aspects.


Assuntos
Relações Interpessoais , Doenças Profissionais/epidemiologia , Saúde Ocupacional/estatística & dados numéricos , Feminino , Humanos , Masculino , Medição de Risco , Segurança , Fatores Sexuais
15.
J Exp Clin Cancer Res ; 35(1): 137, 2016 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-27599543

RESUMO

BACKGROUND: The antimalarial drug Pyrimethamine has been suggested to exert an antitumor activity by inducing apoptotic cell death in cancer cells, including metastatic melanoma cells. However, the dose of Pyrimethamine to be considered as an anticancer agent appears to be significantly higher than the maximum dose used as an antiprotozoal drug. METHODS: Hence, a series of Pyrimethamine analogs has been synthesized and screened for their apoptosis induction in two cultured metastatic melanoma cell lines. One of these analogs, the Methylbenzoprim, was further analyzed to evaluate cell-cycle and the mechanisms of cell death. The effects of Methylbenzoprim were also analyzed in a severe combined immunodeficiency (SCID)-mouse xenotransplantation model. RESULTS: Low dose of Methylbenzoprim was capable of inducing cytotoxic activity and a potent growth-inhibitory effect by arresting cell cycle in S-phase in melanoma cells. Methylbenzoprim was also detected as powerful antineoplastic agents in SCID-mouse although used at very low dose and as a single agent. CONCLUSIONS: Our screening approach led to the identification of a "low cost" newly synthesized drug (methylbenzoprim), which is able to act as an antineoplastic agent in vitro and in vivo, inhibiting melanoma tumor growth at very low concentrations.


Assuntos
Antineoplásicos/administração & dosagem , Melanoma/tratamento farmacológico , Pirimetamina/análogos & derivados , Pirimidinas/administração & dosagem , Animais , Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Caspases/metabolismo , Ciclo Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Proliferação de Células/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Melanoma/metabolismo , Camundongos , Camundongos SCID , Metástase Neoplásica , Pirimidinas/síntese química , Pirimidinas/farmacologia , Ensaios Antitumorais Modelo de Xenoenxerto
16.
FEBS Lett ; 527(1-3): 269-73, 2002 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-12220672

RESUMO

We report a study on the regulation by 2-chloro adenosine (2CA) of a glutamate (Glu) transporter in myogenic C2C12 cells. Long-term 2CA exposition significantly increased the V(max) of the Glu transporter. Moreover, 2CA-treated cells responded to Glu challenge by a rapid and transient increase in their intracellular calcium level. The above reported effects were totally abolished by treating C2C12 cells with the Na(+)-dependent Glu transporter inhibitors DL-threo-b-hydroxyaspartic acid and L-trans-pyrrolidine-2,4-dicarboxylic acid. We propose that the possible link between the Glu uptake increase and the Glu induction of calcium rise could be the depolarizing currents carried by Na(+) coupled with transporter activity.


Assuntos
Sistema X-AG de Transporte de Aminoácidos/metabolismo , Cálcio/metabolismo , Ácido Glutâmico/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Músculo Esquelético/metabolismo , Simportadores/metabolismo , 2-Cloroadenosina/farmacologia , Sistema X-AG de Transporte de Aminoácidos/efeitos dos fármacos , Animais , Ácido Aspártico/análogos & derivados , Ácido Aspártico/farmacologia , Transporte Biológico/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Células Cultivadas , Cicloeximida/farmacologia , Ácidos Dicarboxílicos/farmacologia , Proteínas de Transporte de Glutamato da Membrana Plasmática , Camundongos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Músculo Esquelético/citologia , Músculo Esquelético/efeitos dos fármacos , Inibidores da Síntese de Proteínas/farmacologia , Purinas/metabolismo , Pirrolidinas/farmacologia , Simportadores/efeitos dos fármacos , Regulação para Cima
17.
FEBS Lett ; 566(1-3): 25-9, 2004 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-15147862

RESUMO

The present study was carried out to investigate the potential involvement of cholesterol-rich membrane microdomains in the mobilization of calcium induced by NMDA-receptors (NMDA-R). We herein provide evidence that agents interfering with plasma membrane cholesterol (namely, filipin and methyl-beta-cyclodextrin (Cdex)) inhibit the NMDA-stimulated influx of calcium in hippocampal cells in culture. Filipin-treated cells maintained their morphology and were able to respond with a calcium influx to high K(+) challenge, whereas Cdex altered both cellular parameters. These results suggest that the NMDA-R can be located in cholesterol-rich membrane microdomains or alternatively that the mechanisms coupling their dynamics in the post-synaptic membrane are dependent on the integrity of the microdomains.


Assuntos
Cálcio/metabolismo , Colesterol/metabolismo , Ciclodextrinas/farmacologia , Filipina/farmacologia , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , N-Metilaspartato/antagonistas & inibidores , Neurônios/metabolismo , beta-Ciclodextrinas , Animais , Cálcio/antagonistas & inibidores , Células Cultivadas , Imunofluorescência , Fluorometria/métodos , Gangliosídeo G(M1)/metabolismo , Hipocampo/citologia , Microdomínios da Membrana/efeitos dos fármacos , N-Metilaspartato/farmacologia , Neurônios/citologia , Neurônios/efeitos dos fármacos , Neurônios/ultraestrutura , Cloreto de Potássio/farmacologia , Ratos , Receptores de N-Metil-D-Aspartato/metabolismo
18.
Drug Dev Res ; 45(3-4): 379-386, 1998.
Artigo em Inglês | MEDLINE | ID: mdl-38239500

RESUMO

We investigated the role of the A3 adenosine receptor in cells of the astroglial lineage (both rat primary astrocytes and human astrocytoma ADF cells) by means of the selective A3 agonists N6-(3-iodobenzyl)-adenosine-5'-N-methyluronamide (IB-MECA) and CI-IB-MECA, and by utilizing the selective A3 receptor antagonist MRS1191. Exposure of ADF cells to µM concentrations of either agonist resulted in reduction of cell number, likely due to cell death. In both rat astrocytes and human astrocytoma cells, at concentrations 2-3 orders of magnitude lower (which were not associated with cytotoxicity), these same agonists induced a marked reorganization of the cytoskeleton, with appearance of stress fibers and numerous cell protrusions. Functionally, these morphological changes were associated with cell protection, as demonstrated by a significant reduction of spontaneous apoptosis in A3 agonist-treated cells. To confirm a role for the A3 receptor in this effect, MRS1191 completely counteracted CI-IB-MECA-induced reduction of spontaneous apoptosis. In ADF cells, A3 agonists also induced changes in the intracellular distribution of the anti-apoptotic protein Bcl-XL, which became localized in cell protrusions. Also, this effect was specifically antagonized by MRS1191. These dual actions of A3 agonists in vitro may have important in vivo implications. For example, a robust and acute activation of the A3 receptor following massive adenosine release during ischemia may contribute to brain cell death; conversely, a subthreshold activation of this receptor prior to ischemia may trigger protective mechanisms (i.e., induction of stress fibers and of a Bcl-XL-dependent reorganization of cytoskeleton) making the brain more resistant to subsequent insults ("ischemic tolerance").

19.
Antioxid Redox Signal ; 21(1): 154-76, 2014 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-24450966

RESUMO

SIGNIFICANCE: Skeletal muscle is a highly plastic tissue. Exercise evokes signaling pathways that strongly modify myofiber metabolism and physiological and contractile properties of skeletal muscle. Regular physical activity is beneficial for health and is highly recommended for the prevention of several chronic conditions. In this review, we have focused our attention on the pathways that are known to mediate physical training-induced plasticity. RECENT ADVANCES: An important role for redox signaling has recently been proposed in exercise-mediated muscle remodeling and peroxisome proliferator-activated receptor γ (PPARγ) coactivator-1α (PGC-1α) activation. Still more currently, autophagy has also been found to be involved in metabolic adaptation to exercise. CRITICAL ISSUES: Both redox signaling and autophagy are processes with ambivalent effects; they can be detrimental and beneficial, depending on their delicate balance. As such, understanding their role in the chain of events induced by exercise and leading to skeletal muscle remodeling is a very complicated matter. Moreover, the study of the signaling induced by exercise is made even more difficult by the fact that exercise can be performed with several different modalities, with this having different repercussions on adaptation. FUTURE DIRECTIONS: Unraveling the complexity of the molecular signaling triggered by exercise on skeletal muscle is crucial in order to define the therapeutic potentiality of physical training and to identify new pharmacological compounds that are able to reproduce some beneficial effects of exercise. In evaluating the effect of new "exercise mimetics," it will also be necessary to take into account the involvement of reactive oxygen species, reactive nitrogen species, and autophagy and their controversial effects.


Assuntos
Exercício Físico/fisiologia , Músculo Esquelético/metabolismo , Condicionamento Físico Animal/fisiologia , Animais , Autofagia/fisiologia , Humanos , Oxirredução , PPAR gama/metabolismo , Transdução de Sinais/fisiologia
20.
FEBS J ; 280(20): 5094-108, 2013 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-23953053

RESUMO

It has recently been demonstrated that trimetazidine (TMZ), an anti-ischemic antianginal agent, is also able to improve exercise performance in patients with peripheral arterial disease. TMZ is a metabolic modulator, and the mechanisms underlying its cytoprotective anti-ischemic activity could be ascribed, at least in cardiomyocytes, to optimization of metabolism. However, regarding the cytoprotection exerted by TMZ on skeletal muscle and allowing the improvement of exercise performance, no information is yet available. In the present study, we investigated in detail the protective effects of this drug on in vitro skeletal muscle models of atrophy. Experiments carried out with murine C2C12 myotubes treated with TMZ revealed that this drug could efficiently counteract the cytopathic effects induced by the proinflammatory cytokine tumor necrosis factor-α and by the withdrawal of growth factors. Indeed, TMZ significantly counteracted the reduction in myotube size induced by these treatments. TMZ also increased myosin heavy chain expression and induced hypertrophy in C2C12 myotubes, both effects strongly suggesting a role of TMZ in counteracting atrophy in vitro. In particular, we found that TMZ was able to activate the phosphoinositide 3-kinase-Akt-mammalian target of rapamycin 2 pathway and to reduce the stress-induced transcriptional upregulation of atrogin-1, muscle ring finger protein 1, and myostatin, all of which are key molecules involved in muscle wasting. Moreover, this is the first demonstration that TMZ induces autophagy, a key mechanism involved in muscle mass regulation. On the basis of these results, it can be hypothesized that the improvement in exercise performance previously observed in patients could be ascribed to a cytoprotective mechanism exerted by TMZ on skeletal muscle integrity.


Assuntos
Autofagia/efeitos dos fármacos , Fibras Musculares Esqueléticas/efeitos dos fármacos , Atrofia Muscular/induzido quimicamente , Estresse Fisiológico , Trimetazidina/farmacologia , Animais , Sequência de Bases , Linhagem Celular , Primers do DNA , Camundongos , Fibras Musculares Esqueléticas/metabolismo , Fibras Musculares Esqueléticas/patologia , Atrofia Muscular/etiologia , Cadeias Pesadas de Miosina/metabolismo , Miostatina/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Fator de Necrose Tumoral alfa/farmacologia
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