Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 27
Filtrar
1.
Immun Ageing ; 19(1): 65, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36522763

RESUMO

BACKGROUND: The risk for symptomatic COVID-19 requiring hospitalization is higher in the older population. The course of the disease in hospitalised older patients may show significant variation, from mild to severe illness, ultimately leading to death in the most critical cases. The analysis of circulating biomolecules involved in mechanisms of inflammation, cell damage and innate immunity could lead to identify new biomarkers of COVID-19 severity, aimed to improve the clinical management of subjects at higher risk of severe outcomes. In a cohort of COVID-19 geriatric patients (n= 156) who required hospitalization we analysed, on-admission, a series of circulating biomarkers related to neutrophil activation (neutrophil elastase, LL-37), macrophage activation (sCD163) and cell damage (nuclear cfDNA, mithocondrial cfDNA and nuclear cfDNA integrity). The above reported biomarkers were tested for their association with in-hospital mortality and with clinical, inflammatory and routine hematological parameters. Aim of the study was to unravel prognostic parameters for risk stratification of COVID-19 patients. RESULTS: Lower n-cfDNA integrity, higher neutrophil elastase and higher sCD163 levels were significantly associated with an increased risk of in-hospital decease. Median (IQR) values observed in discharged vs. deceased patients were: 0.50 (0.30-0.72) vs. 0.33 (0.22-0.62) for n-cfDNA integrity; 94.0 (47.7-154.0) ng/ml vs. 115.7 (84.2-212.7) ng/ml for neutrophil elastase; 614.0 (370.0-821.0) ng/ml vs. 787.0 (560.0-1304.0) ng/ml for sCD163. The analysis of survival curves in patients stratified for tertiles of each biomarker showed that patients with n-cfDNA integrity < 0.32 or sCD163 in the range 492-811 ng/ml had higher risk of in-hospital decease than, respectively, patients with higher n-cfDNA integrity or lower sCD163. These associations were further confirmed in multivariate models adjusted for age, sex and outcome-related clinical variables. In these models also high levels of neutrophil elastase (>150 ng/ml) appeared to be independent predictor of in-hospital death. An additional analysis of neutrophil elastase in patients stratified for n-cfDNA integrity levels was conducted to better describe the association of the studied parameters with the outcome. CONCLUSIONS: On the whole, biomarkers of cell-free DNA integrity, neutrophil and macrophage activation might provide a valuable contribution to identify geriatric patients with high risk of COVID-19 in-hospital mortality.

2.
Eur J Nutr ; 56(8): 2457-2466, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-27459881

RESUMO

PURPOSE: Zinc (Zn) plays an essential role in many biological processes including immune response. Impaired Zn status promotes immune dysfunction, and it has been associated with enhanced chronic inflammation during aging. It has been suggested that the measurement of circulating Zn by itself could not reflect the real Zn status of an individual. It is therefore necessary to identify other determinants associated with plasma Zn to better understanding how physiopathological conditions during aging may affect the concentration of this metal. METHODS: We have investigated the association between Zn levels and some biomarkers in 1090 healthy elderly from five European countries to increase the accuracy in the assessment of the Zn status. Stepwise multivariate linear regression models were used to analyze the influence of factors such as age, dietary intake, inflammatory mediators, laboratory parameters and polymorphisms previously associated with Zn homeostasis. RESULTS: Plasma Zn decrement was most strongly predicted by age, while positive correlations were found with albumin, RANTES and Zn intake after adjustment for multiple confounders. HSP70 +1267 AA genotype was an independent factor associated with Zn plasma concentrations. Cu/Zn ratio was positively associated with markers of systemic inflammation and age and negatively associated with albumin serum levels. CONCLUSIONS: Our findings show the most important independent determinants of plasma Zn concentration and Cu/Zn ratio variability in elderly population and suggest that the decline with age of Zn circulating levels is more dependent on physiopathological changes occurring with aging rather than to its nutritional intake.


Assuntos
Envelhecimento , Biomarcadores/sangue , Cobre/sangue , Zinco/sangue , Idoso , Idoso de 80 Anos ou mais , Quimiocina CCL5/genética , Quimiocina CCL5/metabolismo , Estudos de Coortes , Cobre/administração & dosagem , Dieta , Dieta Mediterrânea , Europa (Continente) , Feminino , Técnicas de Genotipagem , Homeostase , Humanos , Inflamação/sangue , Inflamação/fisiopatologia , Masculino , Estado Nutricional , Albumina Sérica/metabolismo , Zinco/administração & dosagem
3.
Aging Clin Exp Res ; 29(3): 353-360, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-27106901

RESUMO

BACKGROUND: Cognitive decline and dementia represent a key problem for public health as they heavily impair social functioning and independent living. The development of new strategies to support recommendations for patients and their caregivers may represent an outstanding step forward. AIMS: To describe the study protocol and methods of "My Mind Project: the effect of cognitive training for elderly" (Grant No. 154/GR-2009-1584108), which investigates, by the use of a multidisciplinary approach, the effects of a comprehensive cognitive training programme on performances in aged subjects with mild-moderate Alzheimer's disease, mild cognitive impairment and normal cognitive functioning. METHODS: The study is a prospective randomized intervention for the assessment of cognitive training effects in three groups of elderly subjects with different cognitive status. A total of 321 elderly people were enrolled in Marche Region, Italy. Each subject was randomly assigned to an experimental group or to a control group. Cognitive performances and biochemical blood markers have also been analysed before cognitive training (baseline), immediately after termination (follow-up 1), after 6 months (follow-up 2) and after 2 years (follow-up 3). DISCUSSION: The results will be useful to identify some efficient programmes for the enhancement of cognitive performance in elderly with and without cognitive decline. CONCLUSION: The application of a non-pharmacological approach in the treatment of elderly with cognitive disorders could have a profound impact on National Health Service.


Assuntos
Doença de Alzheimer/terapia , Disfunção Cognitiva/terapia , Idoso , Doença de Alzheimer/psicologia , Protocolos Clínicos , Disfunção Cognitiva/psicologia , Humanos , Itália , Memória , Estudos Prospectivos
4.
Biogerontology ; 15(1): 65-79, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24243066

RESUMO

Proinflammatory cytokines and heat shock proteins play relevant roles in the pathogenesis of inflammatory diseases. We investigated whether Hsp70 1267 A/G and TNF-α -308 G/A polymorphisms are associated with proinflammatory mediators, zinc status and laboratory parameters in 1,078 healthy elderly from ZincAge study. Hsp70 1267 A/G genotype and allele distribution were similar among various European countries, while a TNF-α genetic heterogeneity was observed between the Northern and the Southern European populations, with a major frequency of the -308 A variant in France, Germany and Poland. We used linear regression models to test additive, dominant or recessive associations of each SNP with proinflammatory mediators, laboratory parameters, metallothioneins and zinc status. Hsp70 1267 A/G SNP, but not TNF-α -308 G/A SNP, influences TNF-α and IL-6 plasma levels under additive, dominant and recessive models (for TNF-α only). An association between Hsp70 1267 A/G SNP and zinc plasma levels was observed in the dominant model. In particular, G allele carriers showed increased circulating pro-inflammatory cytokines and zinc. Moreover, both these SNPs affect creatinine levels suggesting a possible influence on renal function. In conclusion, Hsp70 1267 A/G SNP is associated with pro-inflammatory cytokine production in healthy elderly and might represent a possible determinant of individual susceptibility to inflammatory diseases.


Assuntos
Envelhecimento/metabolismo , Citocinas/sangue , Proteínas de Choque Térmico HSP70/genética , Inflamação/sangue , Polimorfismo de Nucleotídeo Único/genética , Fator de Necrose Tumoral alfa/genética , Zinco/metabolismo , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/genética , Proteína C-Reativa/metabolismo , Europa (Continente) , Feminino , Frequência do Gene/genética , Genótipo , Homeostase/fisiologia , Humanos , Inflamação/genética , Masculino , Metalotioneína/metabolismo , Pessoa de Meia-Idade
5.
Science ; 209(4459): 865-76, 1980 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-17810974

RESUMO

High-sensitivity x-ray measurements with the recently launched Einstein Observatory are having a major impact on wide areas of astronomical research. The x-ray luminosity of young O, B, and A stars and late K and M stars is found to be several orders of magnitude greater than predicted by current theories of coronal heating. Detailed x-ray images and spectra of supernova remnants are providing new information on the temperature, composition, and distribution of material ejected in supernova explosions as well as of the material comprising the interstellar medium. Observations of galaxies are yielding insights on the formation and evolution of stellar systems and galaxies over a wide range of variables. X-ray time variations are being used to probe the underlying energy source in quasars and active galactic nuclei. The distribution of mass in clusters of galaxies is being traced through detailed x-ray images, and the data are being used to classify clusters and trace their formation and evolution. Substantial progress is being made in several areas of cosmological research, particularly in the study of the diffuse x-ray background.

6.
Science ; 161(3841): 564-7, 1968 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-17835675

RESUMO

High-resolution solar x-ray images were obtained with a rocket-borne grazing incidence telescope. The x-ray flare is large in extent, has fine strulctuire, and follows a neutral magnetic line. X-ray emitting coronal links interconnect active regions. The general coronal emission at the limb and several faint regions on the disc are observed.

7.
Science ; 172(3981): 369-72, 1971 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-17756038

RESUMO

X-ray emission from the Cygnus Loop was observed in the energy region around 0.2 to 1 kiloelectronvolt with a collector that focused x-rays along one dimension while scanning across the nebula. The total integrated intensity is 1.3x 10(-8) erg per square centimeter per second. The one-dimensional x-ray structure has the same angular size-about 3 degrees-as the outermost boundaries of the optical filaments. There is no increase in x-ray emission at the center of the nebula nor at the strong feature that is seen in certain radio maps. The x-ray spectrum is consistent with thermal radiation from a hot plasma at a temperature of about 4 x 10(6) degrees K with evidence for a line at 19 angstroms corresponding to the 2p-->1s transition of O VIII.

8.
J Trace Elem Med Biol ; 55: 58-63, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31345366

RESUMO

BACKGROUND: Alzheimer's disease (AD) is the most common age-related neurodegenerative disease. An altered homeostasis of Zinc (Zn) and Copper (Cu), as well as a dysregulated expression of Zn-regulatory proteins have been previously described in AD. Acetylcholinesterase inhibitors (AChEI) are commonly used as AD treatment to improve cognitive function, but their effect on Zn homeostasis is still unexplored. OBJECTIVES: The aims of this study were to define the metal dyshomeostasis in AD patients, to investigate AChEI influence on Zn homeostasis and inflammation, and to analyze the relationship between cognitive impairment at two-year follow-up and metal concentrations, considering AChEI use. METHODS AND RESULTS: 84 Healthy Elderly (HE) and 95 AD patients were enrolled (62 AchEI user and 33 AchEI naïve). HE showed similar plasma Zn and Cu concentrations and Cu/Zn ratio in comparison to AChEI users, but significantly higher Zn level, as well as lower Cu amount and Cu/Zn ratio than AChEI naïve patients. Moreover, AChEI users had increased Zn plasma level, reduced Cu amount, Cu/Zn ratio, and IL1ß concentration and lower Zip2 lymphocytic expression vs. naïve patients. A multiple linear regression analysis showed that the MMSE score decline after two-year follow-up was reduced by AChEI therapy and was positively associated with plasma Zn decrease over time. CONCLUSION: Our data revealed that AChEI use may affect peripheral Zn and Cu homeostasis in AD patients, decrease Cu/Zn ratio demonstrating a general reduction of inflammatory status in patients under AChEI treatment. Finally, AChEI influence on circulating Zn could be implicated in the drug-related slowdown of cognitive decline.


Assuntos
Acetilcolinesterase/metabolismo , Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/farmacologia , Cobre/sangue , Homeostase/efeitos dos fármacos , Zinco/sangue , Idoso , Doença de Alzheimer/sangue , Doença de Alzheimer/enzimologia , Doença de Alzheimer/metabolismo , Inibidores da Colinesterase/administração & dosagem , Cobre/metabolismo , Feminino , Humanos , Inflamação/tratamento farmacológico , Inflamação/metabolismo , Modelos Lineares , Masculino , Zinco/metabolismo
9.
Mol Genet Metab ; 94(1): 98-104, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18249147

RESUMO

Diabetes mellitus is a chronic disease characterized by an overproduction of reactive oxygen species, which perturbs zinc metabolism and promotes the onset of cardiovascular disease (CVD) in diabetic patients. Metallothioneins (MT) are cysteine-rich metal-binding proteins which, by means of their antioxidant and zinc-buffering properties, might prevent the development of diabetic cardiovascular complications. A recent investigation shows that a polymorphism (+647 A/C) in the human MT-1A gene, affects the intracellular zinc ion release (iZnR) from the proteins and is associated with longevity in Italian population. The aim of the present study is to assess the involvement of +647 A/C and +1245 A/G MT1A polymorphisms with the susceptibility to type 2 diabetes (DM2) and cardiovascular complications. The study included 694 old individuals: 242 old healthy controls, 217 DM2 patients without clinical evidence of CVD (DNC) and 235 diabetic patients with diagnosis of CVD (DCVD). +647 A/C MT1A polymorphism, but not the second SNP, was associated with DM2. C allele carriers were more prevalent in DNC and DCVD patients than in control group (OR=1.37, p=0.034; OR=1.54, p=0.002, respectively). C+ carriers was associated with higher glycemia and glycosylated hemoglobin in DCVD patients, but not in DNC or control subjects. No differences in plasma zinc, but a modulation of MT levels and iZnR in PBMCs were observed in DCVD cohort when related to +647 A/C MT1A polymorphism. In summary, this work provides novel evidence on the association of the +647 A/C MT1A polymorphism with DM2. Moreover, C+ carriers in DCVD patients presented a worse glycemic control, a reduced iZnR and a higher MT levels, suggesting a possible role of MT in diabetic cardiovascular complications.


Assuntos
Doenças Cardiovasculares/genética , Complicações do Diabetes/genética , Diabetes Mellitus Tipo 2/genética , Predisposição Genética para Doença , Metalotioneína/genética , Polimorfismo de Nucleotídeo Único , Idoso , Doenças Cardiovasculares/complicações , Diabetes Mellitus Tipo 2/complicações , Feminino , Citometria de Fluxo , Humanos , Masculino , Pessoa de Meia-Idade , Zinco/sangue , Zinco/metabolismo
10.
Exp Gerontol ; 43(5): 423-32, 2008 May.
Artigo em Inglês | MEDLINE | ID: mdl-18316168

RESUMO

Decreased zinc ion availability in ageing is associated with altered immune response. One of the main regulators of zinc availability is metallothionein. Metallothionein induction is under the control of interleukin-6, a pro-inflammatory cytokine whose production is associated with poor ageing. The production of interleukin-6 is controlled, in part, by variability in the -174 nucleotide position. Under conditions of chronic inflammation, such as in ageing, zinc release by metallothionein is limited and may reduce zinc availability. Understanding the precise nature of the interactions between interleukin-6 and metallothioneins will aid in identifying individuals who are at risk of zinc deficiency. In the current study, we used gene arrays to investigate the effects of in vitro zinc supplementation on gene expression in elderly donors with described interleukin-6 and metallothionein 1a polymorphisms. Ingenuity Pathway Analysis identified several zinc-responsive genetic networks uniquely regulated only in elderly individuals with the pro-inflammatory interleukin-6 polymorphism. These include zinc-dependent decreased transcription of pro-inflammatory cytokines and alterations in metabolic regulatory pathways. The genomic effects of zinc increased in significance in the presence of the metallothionein 1a +647 C/A transition, suggesting that the interleukin-6 and metallothionein 1a genes act in a concerted manner to control zinc-regulated gene expression.


Assuntos
Envelhecimento/genética , Interleucina-6/genética , Metalotioneína/genética , Polimorfismo de Nucleotídeo Único/genética , Zinco/fisiologia , Idoso , Feminino , Expressão Gênica , Homeostase , Humanos , Masculino , Metalotioneína/metabolismo , Análise Serial de Proteínas , RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa
11.
Diabetes Res Clin Pract ; 144: 102-110, 2018 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-30142362

RESUMO

AIMS: ZnT8 Arg325Trp polymorphism has been associated with type 2 diabetes (T2DM) susceptibility. The Arg-325 risk variant shows accelerated zinc (Zn) transport kinetic and reduced glucose-stimulated insulin secretion in pancreatic cells. However, it remains unexplored the role of Znt8 polymorphism in the regulation of Zn homeostasis and inflammatory response in peripheral blood mononuclear cells (PBMCs) from T2DM patients. METHODS AND RESULTS: A total of 556 healthy controls and 413 T2DM patients were genotyped for ZnT8 Arg325Trp polymorphism confirming the association of Arg-325 variant with an increased T2DM risk (OR = 1.35 95% C.I: 1.10-1.66; p = 0.0044). Moreover, PBMCs from Arg/Arg T2DM subjects showed increased intracellular free Zn, higher gene expression of Metallothioneins, Znt1, Znt8, Zip2 genes, and reduced Znt4 and Znt7. Higher release of IL-1α, IL-1ß, IFN-γ, IL-12p70 and TNF-α and a reduced IL-10 secretion after lipopolysaccharide (LPS) stimulation were observed in PBMCs from Arg/Arg T2DM carriers as compared to subjects with the Trp variant. CONCLUSIONS: Our data provide evidence of a substantial different Zn homeostasis regulation between Znt8 Arg-325 and Trp-325 carriers in PBMCs from T2DM patients. Moreover, Znt8 Arg-325 risk variant shows an enhanced inflammatory response upon LPS stimulation that might aggravate insulin resistance and the progression of diabetes cardiovascular complications.


Assuntos
Proteínas de Transporte/metabolismo , Citocinas/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Leucócitos Mononucleares/metabolismo , Polimorfismo Genético , Transportador 8 de Zinco/genética , Zinco/metabolismo , Idoso , Idoso de 80 Anos ou mais , Proteínas de Transporte/genética , Estudos de Casos e Controles , Proteínas de Transporte de Cátions/genética , Proteínas de Transporte de Cátions/metabolismo , Diabetes Mellitus Tipo 2/genética , Diabetes Mellitus Tipo 2/patologia , Feminino , Genótipo , Humanos , Masculino , Pessoa de Meia-Idade
12.
Rejuvenation Res ; 10(4): 603-20, 2007 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17985944

RESUMO

Mild zinc deficiency, which is prevalent in vegetarians, diseased individuals, and the general aging population, depresses immunity and increases risk of disease in later life. However, human zinc intervention trials have produced conflicting results, perhaps because many of these trials included young or zinc-sufficient subjects. Since heterogeneity of the adult population may impact on response to dietary zinc, nutrigenomic approaches aimed at understanding the impact of zinc on modulation of gene and protein activities may aid in identifying subsets of the population-in particular the aging population-with increased risk of zinc deficiency who might receive benefit from a dietary zinc intervention and in this way may influence the success of the intervention. In the current study we used nutrigenomic approaches to investigate the impact of age on zinc-regulated gene expression in peripheral blood mononuclear cells. Ingenuity Pathway Analysis (Ingenuity Systems, Redwood City, CA) identified several genetic networks and functional canonical pathways which appeared responsive to zinc that were differentially regulated in young and elderly individuals. These include tryptophan metabolism, eicosanoid signaling, p38 mitogen-activated protein kinase (MAPK) signaling, integrin signaling, purine metabolism, G-protein-coupled receptor signaling, and most significantly, peroxisome proliferator-activated receptor (PPAR) signaling. These data suggest that age impacts strongly on the transcriptional effects of zinc and provides evidence to support the hypothesis that young and elderly individuals may respond differentially to zinc intervention.


Assuntos
Regulação da Expressão Gênica/efeitos dos fármacos , Leucócitos Mononucleares/efeitos dos fármacos , Zinco/farmacologia , Adulto , Fatores Etários , Idoso , Feminino , Humanos , Leucócitos Mononucleares/metabolismo , Masculino , Metalotioneína/genética , Metalotioneína/fisiologia , Pessoa de Meia-Idade , NF-kappa B/genética , NF-kappa B/fisiologia , Análise de Sequência com Séries de Oligonucleotídeos , PPAR alfa/genética , PPAR alfa/fisiologia , Transdução de Sinais
13.
Trends Pharmacol Sci ; 21(6): 205-8, 2000 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-10838605

RESUMO

Infections can cause mortality when the immune system is damaged. The catalytic, structural (in zinc-finger proteins) and regulatory roles of zinc mean that this ion is involved in the maintenance of an effective immune response. Both zinc deficiency and impaired cell-mediated immunity combine during aging to result in increased susceptibility to infection. Dietary supplementation with the recommended daily allowance of zinc for between one and two months decreases the incidence of infection and increases the survival rate following infection in the elderly. This article reviews the biochemical pathways through which zinc might act to increase immunoresistance to infection in the elderly.


Assuntos
Envelhecimento/imunologia , Imunidade/fisiologia , Zinco/fisiologia , Animais , Humanos , Imunidade/efeitos dos fármacos , Zinco/farmacologia , Dedos de Zinco/fisiologia
14.
Mech Ageing Dev ; 121(1-3): 21-35, 2000 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-11164457

RESUMO

Infections may cause mortality in old age due to damaged immune responses. As zinc is required as a catalyst, structural (zinc fingers) and regulatory ion, it is involved in many biological functions, including immune responses. Low zinc ion bioavailability and impaired cell-mediated immunity are common in ageing and may be restored by physiological supplementation with zinc for 1-2 months, impacting upon morbidity and survival. This article reviews the role of zinc in immune efficacy during ageing, and also describes the main biochemical pathways involved in the role of zinc in resistance to infections in ageing in order to better understand the possible causes of immunosenescence.


Assuntos
Envelhecimento/imunologia , Sistema Imunitário/fisiologia , Infecções/imunologia , Zinco/fisiologia , Animais , Citocinas/fisiologia , Humanos , Sistema Imunitário/crescimento & desenvolvimento , Zinco/efeitos adversos , Zinco/uso terapêutico
15.
Mech Ageing Dev ; 106(1-2): 183-204, 1998 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-9883983

RESUMO

Zinc is an essential trace element for many biological functions, including immune functions. Indeed zinc is required for the biological activity of a thymic hormone, called thymulin in its zinc-bound form, important for the maturation and differentiation of T-cells. With advancing age zinc, thymic functions and peripheral immune efficiency show a progressive decline. Supplementing zinc in old age restores them. Zinc is also relevant for liver extrathymic T-cell pathway, being preeminent in old age. Since zinc is also required for metallothioneins (MTs) biological functions, binding zinc with high affinity, aim of the present article is to summarize findings from our laboratory regarding the role of zinc on T-cell pathways, investigating also the possible cause of thymic involution and impaired liver extrathymic T-cell pathway in aging. Partial hepatectomy and liver regeneration are good models for this aim because of the likeness with aging for many immune functions, including thymic functions. MTs levels are increased, other than into the liver, also into the thymus during aging and in young hepatectomized (pHx) mice as compared to young sham controls. MTs may be one of the possible causes of reduced thymic efficiency and impaired liver extrathymic T-cell pathway in old age because of their higher zinc binding affinity rather than thymulin with consequent reduction of the free quota of zinc available for normal cell-mediated immunity. Following that, MTs may contribute to thymic involution and impaired peripheral immune efficiency in aging and in young pHx mice with different roles during the whole life of an organism: protective in young-adult age which may became, at least, dangerous for immune responses in aging. In order to limit or avoid this latter MTs possible role in aging, supplementing physiological zinc may be useful to improve immune responses in old age because of no interference of endogenous zinc on already high thymus MTs levels, but with caution for competition phenomena with copper, as documented in old mice and in syndrome of accelerate aging.


Assuntos
Envelhecimento/imunologia , Metalotioneína/imunologia , Linfócitos T/imunologia , Zinco/imunologia , Animais , Humanos , Sistema Imunitário , Fígado/imunologia , Camundongos , Timo/imunologia , Zinco/fisiologia
16.
Mech Ageing Dev ; 117(1-3): 79-91, 2000 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-10958925

RESUMO

Different age-related immune pathogenetic mechanisms in myasthenia gravis (MG) have been suggested because of restoration after thymectomy (Tx) of altered zinc, thymulin (TH) and T-cell subsets exclusively in early-onset patients (younger <50 years), not in late-onset patients (older >50 years). In this context interleukin-2 (IL-2), interleukin-6 (IL-6) and thymoma are crucial because both involved in MG pathogenesis and correlated with acetylcholine receptors (AchRs) Ab production. Moreover, IL-2 and IL-6 are zinc-dependent, are altered in aging and related with zinc and TH age-dependent declines. Moreover, zinc is relevant for immune efficiency. In order to confirm these different age-related pathogenetic mechanisms further, the role of thymoma, zinc, TH, IL-2 and IL-6 is studied in MG patients with generalized MG with and without thymoma before and 1 month and 1 year after Tx. The high IL-2, IL-6, zinc, and AChR Ab levels observed before Tx are significantly correlated each other in younger MG patients (<50 years) independently by thymoma and in older MG patients (>50 years) with thymoma. No correlations exist in older MG patients without thymoma. Thymulin is not correlated with other parameters considered to be both in younger and older MG patients independently by the thymoma. Thymectomy restores zinc; immune parameters and AChR Ab are exclusively in the younger group, not in the older one. These findings suggest that IL-2 and IL-6, via zinc, rather than TH, may be involved in different age-related pathogenetic mechanisms mainly in early-onset MG. By contrast, thymoma may be involved in MG etiology in late-onset representing, as such, a useful discriminant tool for MG etiology between early and late-onset MG patients. Because autoimmune phenomena may rise in aging, a parallelism with altered immune functions during aging is discussed.


Assuntos
Envelhecimento/imunologia , Interleucina-2/imunologia , Interleucina-6/imunologia , Miastenia Gravis/imunologia , Receptores Colinérgicos/imunologia , Fator Tímico Circulante/imunologia , Timoma/complicações , Neoplasias do Timo/complicações , Zinco/imunologia , Adolescente , Adulto , Idoso , Feminino , Humanos , Interleucina-2/sangue , Interleucina-6/sangue , Masculino , Pessoa de Meia-Idade , Miastenia Gravis/sangue , Miastenia Gravis/complicações , Miastenia Gravis/cirurgia , Timectomia , Fator Tímico Circulante/análise , Timoma/sangue , Timoma/imunologia , Neoplasias do Timo/sangue , Neoplasias do Timo/imunologia , Fatores de Tempo , Zinco/sangue
17.
Science ; 238(4827): 617-9, 1987 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-17816541
18.
Brain Res Bull ; 55(2): 147-53, 2001 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-11470310

RESUMO

Metallothioneins (MTs) (I+II) play pivotal roles in metal-related cell homeostasis because of their high affinity for metals forming clusters. The main functional role of MTs is to sequester and/or dispense zinc participating in zinc homeostasis. Consistent with this role, MT gene expression is transcriptionally induced by a variety of stressing agents to protect cells from reactive oxygen species. In order to accomplish this task, MTs induce the secretion of pro-inflammatory cytokines by immune and brain cells, such as astrocytes, for a prompt response against oxidative stress. These cytokines are in turn involved in new synthesis of MTs in the liver and brain. Such protective mechanism occurs in the young-adult age, when stresses are transient. Stress-like condition is instead constant in the old age, and this causes continuous stealing of intracellular zinc by MTs and consequent low bioavailability of zinc ions for immune, endocrine, and cerebral functions. Therefore, a protective role of zinc-bound MTs (I+II) during ageing can be questioned. Because free zinc ions are required for optimal efficiency of the immune-endocrine-nervous network, zinc-bound MTs (I+II) may play a different role during ageing, switching from a protective to a deleterious one in immune, endocrine, and cerebral activities. Physiological zinc supply, performed cautiously, can correct deficiencies in the immune-neuroendocrine network and can improve cognitive performances during ageing and accelerated ageing. Altogether these data indicate that zinc-bound MTs (I+II) can be considered as novel potential markers of ageing.


Assuntos
Envelhecimento/metabolismo , Encéfalo/metabolismo , Metalotioneína/metabolismo , Zinco/metabolismo , Envelhecimento/patologia , Animais , Biomarcadores , Encéfalo/patologia , Encéfalo/fisiopatologia , Humanos , Sistema Imunitário/metabolismo , Sistema Imunitário/fisiopatologia , Sistemas Neurossecretores/metabolismo , Sistemas Neurossecretores/fisiopatologia , Estresse Oxidativo/fisiologia
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa