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1.
Scand J Med Sci Sports ; 25 Suppl 2: 33-9, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26083700

RESUMO

This study investigated features of skeletal muscle ageing in elderly individuals having previously undergone unilateral total knee arthroplasty (TKA) and whether markers of sarcopenia could be mitigated by a 12-week alpine skiing intervention. Novel biomarkers agrin, indicative of neuromuscular junction (NMJ) degeneration, tumor suppressor protein p53, associated with muscle atrophy, and a new ultrasound-based muscle architecture biomarker were used to characterize sarcopenia. Participant details and study design are presented by Kösters et al. (2015). The results of this study show that NMJ degeneration is widespread among active septuagenarians previously subjected to TKA: all participants showed elevated agrin levels upon recruitment. At least 50% of individuals were identified as sarcopenic based on their muscle architecture, supporting the hypothesis that NMJ alterations precede sarcopenia. Notably, sarcopenia was strongly associated with the expression of p53, which seems to confirm its validity as a biomarker of muscle atrophy. Training did not significantly modify any of these biomarkers. In view of the lack of accretion of muscle mass in response to the alpine skiing intervention, we hypothesize that local muscle inflammation and oxidative stress may have blunted the anabolic response to training and promoted muscle breakdown in this elderly post-TKA population.


Assuntos
Envelhecimento/metabolismo , Agrina/metabolismo , Artroplastia do Joelho , Osteoartrite do Joelho/cirurgia , Músculo Quadríceps/metabolismo , Sarcopenia/metabolismo , Esqui , Proteína Supressora de Tumor p53/metabolismo , Idoso , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/metabolismo , Atrofia Muscular/metabolismo , Doenças da Junção Neuromuscular/metabolismo , Músculo Quadríceps/diagnóstico por imagem , Sarcopenia/diagnóstico por imagem , Ultrassonografia
2.
Scand J Med Sci Sports ; 25 Suppl 2: 40-8, 2015 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-26083701

RESUMO

We investigated the effect of alpine skiing for 12 weeks on skeletal muscle characteristics and biomarkers of glucose homeostasis and cardiovascular risk factors. Twenty-three patients with a total knee arthroplasty (TKA) were studied 2.9 ± 0.9 years (mean ± SD) after the operation. Fourteen patients participated in the intervention group (IG) and nine in the control group (CG). Blood samples and muscle biopsies were obtained before (PRE) and 7.3 ± 0.8 days after (POST) the intervention, and blood samples again after a retention (RET) phase of 8 weeks. With skiing, glucose homeostasis improved in IG (decrease in fasting insulin, increase in muscle glycogen) but not in CG. Fiber type distribution and size, as well as capillary density and number of capillaries around the fibers (CAF), were not different between the operated and the non-operated leg in either group. The relative number of type I fibers increased with skiing in IG with no change in CG. Inflammatory biomarkers, plasma lipids, and mitochondrial proteins and activity did not change. Alpine skiing is metabolically beneficial and can be used as a training modality by elderly people with TKA.


Assuntos
Artroplastia do Joelho , Glicemia/metabolismo , Glicogênio/metabolismo , Fibras Musculares Esqueléticas/metabolismo , Osteoartrite do Joelho/cirurgia , Esqui , Idoso , Proteína C-Reativa/imunologia , Capilares , HDL-Colesterol/metabolismo , LDL-Colesterol/metabolismo , Citocinas/imunologia , Feminino , Humanos , Inflamação , Insulina/metabolismo , Masculino , Pessoa de Meia-Idade , Proteínas Mitocondriais/metabolismo , Fibras Musculares Esqueléticas/citologia , Fibras Musculares de Contração Lenta/citologia , Fibras Musculares de Contração Lenta/metabolismo , Músculo Esquelético/irrigação sanguínea , Músculo Esquelético/metabolismo , Triglicerídeos/metabolismo
3.
Exp Gerontol ; 54: 14-20, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-24487345

RESUMO

Centenarians are rare and exceptional individuals characterized by a peculiar phenotype. They are the best example of healthy aging in humans as most of them have escaped or substantially delayed the onset of major age-related diseases. Within this scenario, the purpose of the present work was to understand if immune status is associated with survival and health status in centenarians. To this aim, 116 centenarians were concomitantly characterized for their immunological, health and functional status, and followed-up for five-year survival. On the basis of previous knowledge we focused on a core of fundamental and basic immune parameters (number of leukocytes, monocytes, total lymphocytes, CD3(+) T lymphocytes, CD4(+) helper T lymphocytes, CD8(+) cytotoxic T lymphocytes, CD19(+) B lymphocytes and plasma levels of IgM), and the most important findings can be summarized as follows: i. a hierarchical cluster analysis was able to define Cluster1 (88 centenarians) and Cluster2 (28 centenarians) characterized by low and high values of all these immune parameters, respectively; ii. centenarians of Cluster2 showed a statistically longer five-year survival and more favorable values of other important immune (naïve, activated/memory and effector/memory T cells) and metabolic (glycemia, insulin and HOMA-IR) parameters, in accord with previous observations that centenarians have a peculiar immune profile, a preserved insulin pathway and a lower incidence of type 2 diabetes; and iii. unexpectedly, parameters related to frailty, as well as functional and cognitive status, did not show any significant correlation with the immune clustering, despite being capable per se of predicting survival. In conclusion, high values of basic immunological parameters and important T cell subsets correlate with five-year survival in centenarians, independent of other phenotypic characteristics. This unexpected biological scenario is compatible with the general hypothesis that in centenarians a progressive disconnection and loss of biological coherence among the different functions of the body occur, where survival/mortality result from the failure of any of these domains which apparently follow an independent age-related trajectory.


Assuntos
Imunidade Adaptativa/fisiologia , Nível de Saúde , Idoso de 80 Anos ou mais , Linfócitos B/imunologia , Análise por Conglomerados , Diabetes Mellitus Tipo 2/imunologia , Feminino , Idoso Fragilizado , Humanos , Memória Imunológica/imunologia , Estimativa de Kaplan-Meier , Masculino , Linfócitos T/imunologia
4.
Curr Pharm Des ; 16(7): 802-13, 2010.
Artigo em Inglês | MEDLINE | ID: mdl-20388091

RESUMO

Human aging and longevity are complex and multi-factorial traits that result from a combination of environmental, genetic, epigenetic and stochastic factors, each contributing to the overall phenotype. The multi-factorial process of aging acts at different levels of complexity, from molecule to cell, from organ to organ systems and finally to organism, giving rise to the dynamic "aging mosaic". At present, an increasing amount of experimental data on genetics, genomics, proteomics and other -omics are available thanks to new high-throughput technologies but a comprehensive model for the study of human aging and longevity is still lacking. Systems biology represents a strategy to integrate and quantify the existing knowledge from different sources into predictive models, to be later tested and then implemented with new experimental data for validation and refinement in a recursive process. The ultimate goal is to compact the new acquired knowledge into a single picture, ideally able to characterize the phenotype at systemic/organism level. In this review we will briefly discuss the aging phenotype in a systems biology perspective, showing four specific examples at different levels of complexity, from a systemic process (inflammation) to a cascade-process pathways (coagulation) and from cellular organelle (proteasome) to single gene-network (PON-1), which could also represent targets for anti-aging strategies.


Assuntos
Envelhecimento/fisiologia , Longevidade/fisiologia , Biologia de Sistemas , Fatores Etários , Desenho de Fármacos , Humanos , Modelos Biológicos
5.
Neuroimmunomodulation ; 15(4-6): 224-40, 2008.
Artigo em Inglês | MEDLINE | ID: mdl-19047800

RESUMO

At present, individuals can live up to 80-120 years, a time much longer than that of our ancestors, as a consequence of the improvements in life conditions and medical care. Thus, the human immune system has to cope with a lifelong and evolutionarily unpredicted exposure to a variety of antigens, which are at the basis of profound age-related changes globally indicated as immunosenescence, a multifaceted phenomenon that increases morbidity and mortality due to infections and age-related pathologies. The major changes occurring during immunosenescence are the result of the accumulation of cellular, molecular defects and involutive phenomena (such as thymic involution) occurring concomitantly to a hyperstimulation of both innate and adaptive immunity (accumulation of expanded clones of memory and effector T cells, shrinkage of the T cell receptor repertoire, progressive activation of macrophages), and resulting in a low-grade, chronic state of inflammation defined as inflammaging. It is unknown whether inflammaging, which represents a risk factor for most age-related pathologies, is a cause or rather an effect of the aging process. In this complex scenario, the role of genetic background likely represents a fundamental variable to attain successful aging and longevity. Accordingly, centenarians seem to be equipped with gene variants that allow them to optimize the balance between pro- and anti-inflammatory molecules, and thus to minimize the effects of the lifelong exposure to environmental insults and stressors. The remarkable features of the genetics of aging and longevity are reviewed, stressing the unexpected and unusual results obtained regarding such a postreproductive type of genetics.


Assuntos
Envelhecimento/imunologia , Fenômenos Imunogenéticos , Longevidade/fisiologia , Tecido Adiposo/fisiologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Antígenos Virais/imunologia , Atrofia , Infecções por Citomegalovirus/imunologia , Infecções por Citomegalovirus/fisiopatologia , Infecções por Vírus Epstein-Barr/imunologia , Infecções por Vírus Epstein-Barr/fisiopatologia , Humanos , Imunidade Celular/genética , Imunidade Celular/imunologia , Imunocompetência/genética , Imunocompetência/imunologia , Infecções/genética , Infecções/imunologia , Inflamação/genética , Inflamação/imunologia , Interleucinas/genética , Interleucinas/imunologia , Interleucinas/fisiologia , Longevidade/genética , Longevidade/imunologia , Pessoa de Meia-Idade , Neoplasias/genética , Neoplasias/imunologia , Subpopulações de Linfócitos T/imunologia , Timo/patologia
6.
Expert Opin Biol Ther ; 8(9): 1393-405, 2008 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-18694357

RESUMO

BACKGROUND: The aging phenotype in humans is very heterogeneous and can be described as a complex mosaic resulting from the interaction of a variety of environmental, stochastic and genetic-epigenetic variables. Therefore, each old person must be considered as a singleton, and consequently the definition of 'aging phenotype' is very difficult. OBJECTIVE: We discuss the phenotype of centenarians, the best example of successful aging, as well as other models exploited to study human aging and longevity, such as families enriched in long-living subjects, twins and cohorts of unrelated subjects. METHODS: A critical review of literature available until March 2008. CONCLUSIONS: No single model can be considered the gold standard for the study of aging and longevity, instead the combination of results obtained from different models must be considered in order to better understand these complex phenomena. We propose that a systems biology concept such as that of 'bow-tie' architecture, useful for managing information flow, could help in this demanding task.


Assuntos
Envelhecimento , Longevidade , Modelos Biológicos , Idoso , Idoso de 80 Anos ou mais , Humanos , Fenótipo
7.
Evid Based Complement Alternat Med ; 4(2): 181-90, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17549234

RESUMO

Curcumin, the yellow pigment from the rhizoma of Curcuma longa, is a widely studied phytochemical which has a variety of biological activities: anti-inflammatory and anti-oxidative. In this review we discuss the biological mechanisms and possible clinical effects of curcumin treatment on cancer therapy, and neurodegenerative diseases such as Alzheimer's Disease, with particular attention to the cell death processes induced by curcumin. Since oxidative stress and inflammation are major determinants of the aging process, we also argue that curcumin can have a more general effect that slows down the rate of aging. Finally, the effects of curcumin can be described as xenohormetic, since it activates a sort of stress response in mammalian cells.

8.
Free Radic Res ; 40(12): 1303-23, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17090420

RESUMO

Many epidemiological data indicate the presence of a strong familial component of longevity that is largely determined by genetics, and a number of possible associations between longevity and allelic variants of genes have been described. A breakthrough strategy to get insight into the genetics of longevity is the study of centenarians, the best example of successful ageing. We review the main results regarding nuclear genes as well as the mitochondrial genome, focusing on the investigations performed on Italian centenarians, compared to those from other countries. These studies produced interesting results on many putative "longevity genes". Nevertheless, many discrepancies are reported, likely due to the population-specific interactions between gene pools and environment. New approaches, including large-scale studies using high-throughput techniques, are urgently needed to overcome the limits of traditional association studies performed on a limited number of polymorphisms in order to make substantial progress to disentangle the genetics of a trait as complex as human longevity.


Assuntos
Envelhecimento/genética , Genes , Longevidade/genética , Idoso de 80 Anos ou mais , Animais , Apolipoproteína E4/genética , Apolipoproteínas/genética , Arildialquilfosfatase/genética , Clusterina/genética , Citocinas/genética , DNA Mitocondrial/genética , Humanos , Inflamação/genética , Fator de Crescimento Insulin-Like I/genética , Poli(ADP-Ribose) Polimerases/genética , Polimorfismo Genético , Complexo de Endopeptidases do Proteassoma/fisiologia , Superóxido Dismutase/genética , Proteína Supressora de Tumor p53/genética
9.
Biogerontology ; 7(5-6): 437-47, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-17028933

RESUMO

Immunosenescence features, such as thymic involution, alteration of T-cell repertoire, autoimmunity and accumulation of memory/effector T cells, may be the result, at least in part, of a zinc deficiency, which is often observed during ageing. Zinc, as essential trace element, affects the immune system function and it is an important regulator of apoptosis of immune cells. In this study we addressed the question whether zinc supplementation in vitro at physiological doses can affect spontaneous and oxidative stress-induced apoptosis in peripheral blood mononuclear cells from subjects of three different age groups: young (mean age 28 years), old (mean age 72 years) and nonagenarians. We studied different parameters related to apoptosis (phosphatydilserine exposure, mitochondrial membrane potential, caspase 3 cleavage) and we found that zinc, while decreasing spontaneous apoptosis, can increase oxidative stress-induced apoptosis in an age-related fashion, being this effect more evident in nonagenarians than in old or young subjects. In particular, zinc can increase late apoptosis/necrosis, a phenomenon that could trigger unnecessary inflammation in vivo. We surmise that these age-associated alterations in susceptibility to apoptosis may be due to a different effect of zinc on T cell subsets, that are altered in very old people, and finally that the zinc deficiency, which is often observed in aged subjects, could be a compensatory mechanism to counteract the inflammatory status of the elderly.


Assuntos
Envelhecimento/sangue , Apoptose/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Sulfato de Zinco/farmacologia , Zinco/sangue , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/imunologia , Caspase 3/metabolismo , Células Cultivadas , Ativação Enzimática/efeitos dos fármacos , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , Leucócitos Mononucleares/patologia , Masculino , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Pessoa de Meia-Idade , Estresse Oxidativo , Valores de Referência , Zinco/deficiência
10.
Curr Pharm Des ; 12(24): 3161-71, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16918441

RESUMO

In this article we summarise present knowledge on the role of pro-inflammatory cytokines on chronic inflammation leading to organismal aging, a phenomenon we proposed to call "inflamm-aging". In particular, we review genetic data regarding polymorphisms of genes encoding for cytokines and proteins involved in natural immunity (such as Toll-like Receptors and Heat Shock Proteins) obtained from large population studies including young, old and very old people in good health status or affected by age-related diseases such as Alzheimer's Disease and Type II Diabetes. On the whole, despite some controversial results, the available data are in favour of the hypothesis that pro-inflammatory cytokines play an important role in aging and longevity. Further, we present a possible hypothesis to reconcile energetic dysfunction, including mitochondria, and inflamm-aging. New perspectives for future studies, including phylogenetic studies in animal models and in silico studies on mathematical and bioinformatic models inspired by the systems biology approach, are also proposed.


Assuntos
Envelhecimento/fisiologia , Citocinas/fisiologia , Inflamação/fisiopatologia , Mitocôndrias/fisiologia , Animais , Citocinas/genética , Humanos , Inflamação/genética , Filogenia , Polimorfismo Genético/genética , Biologia de Sistemas/métodos
11.
Mech Ageing Dev ; 127(6): 560-6, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16516272

RESUMO

Several alterations in immune function and a concomitant progressive increase in pro-inflammatory status are the major characteristics of ageing process. Cytokines play a key role during ageing acting both in regulatory communication among cells and in effector activity during an immune response. The impact of age on intracellular Type 1 (IFN-gamma and TNF-alpha) and Type 2 (IL-4) cytokines, after stimulation with PMA/ionomycin, was determined in three CD4+ T subsets, i.e. CD95- CD28+ (virgin), CD95+ CD28+ (activated/memory), and CD95+ CD28- (effector/memory) from 47 subjects aged between 21 and 99 years. The percentage of IFN-gamma positive cells significantly decreased in virgin CD4+ subset both in old and nonagenarian subjects, as well as in activated/memory T cells from old in comparison with young subjects. The percentage of TNF-alpha positive cells significantly decreased in activated/memory CD4+ subset from old people. Regarding Type 2 cytokines, IL-4 positive cells significantly increased in activated/memory CD4+ subset from nonagenarians. On the whole our data indicate that: (1) different Type 1 and Type 2 cytokine-positive CD4+ T subsets are differently affected by ageing process; (2) activated/memory T cells appear to be the most affected subset; (3) a shift towards an increased role of Type 2 cytokines and a diminished role of Type 1 cytokines emerges with ageing.


Assuntos
Envelhecimento/imunologia , Linfócitos T CD4-Positivos/imunologia , Citocinas/metabolismo , Memória Imunológica/imunologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Biomarcadores/metabolismo , Antígenos CD28/metabolismo , Linfócitos T CD4-Positivos/metabolismo , Citometria de Fluxo , Humanos , Inflamação/imunologia , Interferon gama/metabolismo , Interleucina-4/metabolismo , Pessoa de Meia-Idade , Subpopulações de Linfócitos T/imunologia , Subpopulações de Linfócitos T/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Receptor fas/metabolismo
12.
Mech Ageing Dev ; 126(8): 839-44, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15992607

RESUMO

p66(shc-/-) mice exhibit prolonged lifespan and increased resistance to oxidative and hypoxic stress. To investigate p66(shc) involvement in human longevity, p66(shc) mRNA and protein were evaluated in fibroblasts from young people, elderly and centenarians, exposed to oxidative or hypoxic stress. Unexpectedly, centenarians showed the highest basal levels of p66(shc). Oxidative stress induced p66(shc) in all samples. At variance, hypoxic stress caused p66(shc) reduction only in cells from centenarians. These changes occurred in absence of any modification of p66(shc) promoter methylation pattern. Intriguingly, in cells from centenarians, p66(shc) induction was affected by p53 codon 72 polymorphism. Thus, cells from centenarians present a peculiar regulation of p66(shc), suggesting that its role in mammalian longevity is more complex than previously thought.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal/biossíntese , Fibroblastos/metabolismo , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Apoptose , Western Blotting , Células Cultivadas , Códon , DNA/química , DNA/metabolismo , Metilação de DNA , DNA Complementar/metabolismo , Desferroxamina/farmacologia , Desoxirribose/metabolismo , Humanos , Hipóxia , Longevidade , Pessoa de Meia-Idade , Estresse Oxidativo , Regiões Promotoras Genéticas , RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Proteínas Adaptadoras da Sinalização Shc , Proteína 1 de Transformação que Contém Domínio 2 de Homologia de Src , Sulfitos/química , Transcrição Gênica , Proteína Supressora de Tumor p53/metabolismo
13.
Exp Gerontol ; 39(10): 1459-65, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15501015

RESUMO

BACKGROUND: Non-organ-specific autoantibodies are present in centenarians without evidence of autoimmune diseases but conflicting or no data on anti-phospholipid and anti-phospholipid binding proteins were reported. OBJECTIVE: To investigate the presence and antigen specificity of anti-phospholipid and anti-phospholipid binding proteins in centenarians. METHODS: Seventy-seven centenarians, 70 adult controls, 65 unselected elderly subjects, and 38 old SENIEUR volunteers were investigated. Anti-cardiolipin, anti-human beta 2 glycoprotein I, and lupus anticoagulant were detected. Antigen specificity was assayed against plates coated with anionic, neutral and cationic phospholipids and beta 2 glycoprotein I-dependence was also evaluated. RESULTS: 54.3% of the centenarians were positive for IgG and 8.6% for IgM anti-beta 2 glycoprotein I antibodies, while only 20.7% centenarians were positive for anti-cardiolipin IgG and 2.59% for IgM; none resulted positive for lupus anticoagulant. Anti-cardiolipin positive sera cross-reacted with negatively charged phospholipids and displayed decreased binding to serum-free cardiolipin-coated plates that was restored by human beta 2 glycoprotein I or fetal calf serum. CONCLUSIONS: Centenarians display high reactivity against human beta 2 glycoprotein I but low binding to the bovine molecule in the anti-cardiolipin assay. In spite of the presence of antibodies comparable to those found in patients with the anti-phospholipid syndrome, no vascular events were reported suggesting the presence of unknown protective factors and/or the lack of triggering factors.


Assuntos
Envelhecimento/imunologia , Autoanticorpos/sangue , Glicoproteínas/imunologia , Idoso , Idoso de 80 Anos ou mais , Cardiolipinas/imunologia , Epitopos , Feminino , Humanos , Imunoglobulina G/sangue , Imunoglobulina M/sangue , Inibidor de Coagulação do Lúpus/sangue , Masculino , beta 2-Glicoproteína I
14.
Cell Death Differ ; 11(9): 962-73, 2004 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-15131588

RESUMO

A common arginine to proline polymorphism is harboured at codon 72 of the human p53 gene. In this investigation, we found that fibroblasts and lymphocytes isolated from arginine allele homozygote centenarians and sexagenarians (Arg+) undergo an oxidative-stress-induced apoptosis at a higher extent than cells obtained from proline allele carriers (Pro+). At variance, the difference in apoptosis susceptibility between Arg+ and Pro+ is not significant when cells from 30-year-old people are studied. Further, we found that Arg+ and Pro+ cells from centenarians differ in the constitutive levels of p53 protein and p53/MDM2 complex, as well as in the levels of oxidative stress-induced p53/Bcl-xL complex and mitochondria-localised p53. Consistently, all these differences are less evident in cells from 30-year-old people. Finally, we investigated the in vivo functional relevance of the p53 codon 72 genotype in a group of old patients (66-99 years of age) affected by acute myocardial ischaemia, a clinical condition in which in vivo cell death occurs. We found that Arg+ patients show increased levels of Troponin I and CK-MB, two serum markers that correlate with the extent of the ischaemic damage in comparison to Pro+ patients. In conclusion, these data suggest that p53 codon 72 polymorphism contributes to a genetically determined variability in apoptotic susceptibility among old people, which has a potentially relevant role in the context of an age-related pathologic condition, such as myocardial ischaemia.


Assuntos
Apoptose , Códon , Genes p53 , Isquemia , Proteína Supressora de Tumor p53/fisiologia , Adulto , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Alelos , Arginina , Western Blotting , Morte Celular , Creatina Quinase/sangue , Creatina Quinase Forma MB , Relação Dose-Resposta a Droga , Feminino , Fibroblastos/metabolismo , Citometria de Fluxo , Genótipo , Homozigoto , Humanos , Imunoprecipitação , Isoenzimas/sangue , Leucócitos/metabolismo , Linfócitos/metabolismo , Masculino , Potenciais da Membrana , Microscopia de Fluorescência , Pessoa de Meia-Idade , Isquemia Miocárdica/patologia , Estresse Oxidativo , Polimorfismo Genético , Prolina , Proteínas Proto-Oncogênicas c-bcl-2 , Análise de Regressão , Serina/química , Fatores de Tempo , Transfecção , Troponina I/sangue , Proteína bcl-X
15.
Cell Death Differ ; 10(2): 163-74, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12700644

RESUMO

The onset of resistance to drug-induced apoptosis of tumour cells is a major problem in cancer therapy. We studied a drug-selected clone of promyelocytic HL-60 cells, called HCW-2, which display a complex resistance to a wide variety of apoptosis-inducing agents and we found that these cells show a dramatic increase in the expression of heat shock proteins (Hsps) 70 and 27, while the parental cell line does not. It is known that stress proteins such as Hsps can confer resistance to a variety of damaging agents other than heat shock, such as TNF-alpha, monocyte-induced cytotoxicity, and also play a role in resistance to chemotherapy. This elevated expression of Hsps is paralleled by an increased activity of mitochondrial metabolism and pentose phosphate pathway, this latter leading to high levels of glucose-6-phosphate dehydrogenase and, consequently, of glutathione. Thus, the apoptotic-deficient phenotype is likely because of the presence of high levels of stress response proteins and GSH, which may confer resistance to apoptotic agents, including chemotherapy drugs. Moreover, the fact that in HCW-2 cells Hsp70 are mainly localised in mitochondria may account for the increased performances of mitochondrial metabolism. These observations could have some implications for the therapy of cancer, and for the design of combined strategies that act on antioxidant defences of the neoplastic cell.


Assuntos
Apoptose , Mitocôndrias/metabolismo , Oxirredução , Células Clonais , DNA Mitocondrial/análise , Resistência a Múltiplos Medicamentos/genética , Glucosefosfato Desidrogenase/metabolismo , Glutationa/biossíntese , Células HL-60 , Proteínas de Choque Térmico HSP70/metabolismo , Humanos , Mitocôndrias/ultraestrutura , Via de Pentose Fosfato , Fenótipo , Proteínas Proto-Oncogênicas c-bcl-2/análise
16.
Exp Gerontol ; 37(2-3): 301-8, 2002.
Artigo em Inglês | MEDLINE | ID: mdl-11772516

RESUMO

As a consequence of inflammatory stimuli (such as TNFalpha and IFNgamma), some constitutive subunits of the proteasome, the principal mediator of nonlysosomal protein degradation, are replaced with other subunits, the large multifunctional proteases LMP2 and LMP7, thus originating the immunoproteasome. An age-related alteration of proteasome activity and susceptibility to TNFalpha-induced apoptosis, in which LMP2 and the nuclear factor (NF)-kappaB activation play an important role has been recently reported. In this paper, we investigated the possible influence of two LMP2 and LMP7 polymorphisms on susceptibility to TNFalpha-induced apoptosis. Our data show that an increase in susceptibility to TNFalpha-induced apoptosis is evident in long-lived people (aged >88 years) in comparison to young individuals. Moreover, the modulation of LMP2 codon 60 polymorphism on TNFalpha-induced apoptosis is evident in long-lived subjects. Genotyping of 311 young people and 157 nonagenarians and centenarians revealed no changes in LMP2 codon 60 genotype frequency distribution. No correlation with TNFalpha-induced apoptosis and no difference in frequency between young people and nonagenarians/centenarians was observed when the LMP7 nucleotide 145 polymorphism was studied.


Assuntos
Envelhecimento/genética , Apoptose/genética , Cisteína Endopeptidases , Complexo Principal de Histocompatibilidade/genética , Complexos Multienzimáticos , Polimorfismo Genético , Proteínas/genética , Adulto , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/imunologia , Apoptose/imunologia , Células Cultivadas , Humanos , Leucócitos Mononucleares/citologia , Leucócitos Mononucleares/efeitos dos fármacos , Leucócitos Mononucleares/imunologia , Longevidade , Complexo de Endopeptidases do Proteassoma , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/farmacologia
17.
FEBS Lett ; 492(1-2): 9-13, 2001 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-11248228

RESUMO

A new perspective is emerging indicating that mitochondria play a critical role in aging not only because they are the major source and the most proximal target of reactive oxygen species, but also because they regulate stress response and apoptosis. Recent literature indicates that, in response to stress, a variety of molecules translocate to and localise in mitochondria. These molecules are likely to interact with each other, in order to mediate mitochondria/nucleus cross-talk and to regulate apoptosis. We surmise that an integration of signals in multimolecular complexes occurs at mitochondrial level. These phenomena can be of critical importance for human aging and longevity.


Assuntos
Envelhecimento/metabolismo , Longevidade/fisiologia , Mitocôndrias/metabolismo , Apoptose , Humanos , Espécies Reativas de Oxigênio/metabolismo
19.
Curr Protoc Cytom ; Chapter 9: Unit 9.14, 2001 May.
Artigo em Inglês | MEDLINE | ID: mdl-18770751

RESUMO

Changes in membrane potential have long been known to represent early activation events. This unit presents very recent developments in both fluorescent probes and functional applications and demonstrates the use of the JC-1 probe for measuring mitochondrial membrane potential by flow cytometry. A valuable component of this measurement system is the possibility of making quantitative measurements of changes in membrane potential.


Assuntos
Benzimidazóis/farmacologia , Carbocianinas/farmacologia , Separação Celular/métodos , Citometria de Fluxo/métodos , Potencial da Membrana Mitocondrial , Animais , Apoptose , Linhagem Celular Tumoral , Corantes Fluorescentes/farmacologia , Humanos , Mitocôndrias/metabolismo
20.
J Invest Dermatol ; 115(5): 835-41, 2000 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11069621

RESUMO

Carboxyfullerene, a water-soluble carboxylic acid derivative of a fullerene, which acts as a free-radical scavenger, was investigated as a protective agent against ultraviolet-light-induced damage in human keratinocytes. First, we demonstrate that carboxyfullerene is not cytotoxic for these cells. In addition, this compound significantly reduces the ultraviolet-B-induced inhibition of keratinocyte proliferation and protects keratinocytes from apoptosis caused by ultraviolet B irradiation in a time- and dose-dependent fashion. Furthermore, the percentage of cells with depolarized mitochondria is significantly lower in ultraviolet-B-irradiated keratinocytes pretreated with carboxyfullerene than in cells provided with diluent alone. Carboxyfullerene also protects human keratinocytes from apoptosis induced by exposure to deoxy-D-ribose, a sugar that causes cell death through a pathway involving oxidative stress. On the other hand, ultraviolet B downregulates bcl-2 levels in human keratinocytes, and carboxyfullerene fails to prevent this effect. These results suggest that carboxy- fullerene protects human keratinocytes from ultraviolet B damage possibly via a mechanism interfering with the generation of reactive oxygen species from depolarized mitochondria without the involvement of bcl-2.


Assuntos
Carbono/farmacologia , Ácidos Carboxílicos/farmacologia , Fulerenos , Queratinócitos/citologia , Protetores contra Radiação/farmacologia , Raios Ultravioleta , Apoptose/efeitos dos fármacos , Apoptose/efeitos da radiação , Desoxirribose/farmacologia , Citometria de Fluxo , Humanos , Membranas Intracelulares/fisiologia , Potenciais da Membrana , Mitocôndrias , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo
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