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1.
Appetite ; 58(1): 188-95, 2012 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21986182

RESUMO

This study aimed to identify factors associated with taste acuity in healthy older European adults aged 55-87 years, employing a factorial independent design to recruit older adults from centres in France, Italy and United Kingdom. Adults aged 70-87 years (N=387) were recruited in Rome (Italy) (n=108) and Grenoble (France) (n=91) and aged 55-70 years in Northern Ireland (United Kingdom) (n=93) and Clermont-Ferrand (C-F) (France) (n=95). A signal detection theory (SDT) approach was used for detection threshold assessment of the four basic tastes (salt; sweet; bitter; and, sour). Trial data were converted to R-indices. Diet was assessed by means of four day food diaries. Dietary data were converted using WISP and then reduced, using a principal components analysis, to four components: Component 1 'high fat and salt'; Component 2 'high vitamins and fibre'; Component 3 'high fat and carbohydrate'; and, Component 4 'high trace elements'. Socio-demographic information was collected by self report survey. Four separate regression analyses were carried out, one for each of the four basic taste qualities (sweet; sour; bitter; salt). Mean ROC scores for each taste quality were the response variables and age, sex, country, social class and dietary components were predictor variables. The main predictors of taste acuity were age, sex, social class and country, which had differential effects for each taste quality. These data suggest that socio-demographic and cultural factors should be taken into account when considering taste acuity in older people.


Assuntos
Comportamento Alimentar , Limiar Gustativo , População Branca , Idoso , Idoso de 80 Anos ou mais , Dieta , Registros de Dieta , Feminino , França , Humanos , Irlanda , Masculino , Pessoa de Meia-Idade , Análise de Regressão , Cidade de Roma , Detecção de Sinal Psicológico , Percepção Gustatória , Reino Unido
2.
Int J Vitam Nutr Res ; 81(5): 277-85, 2011 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-22419198

RESUMO

An increased rate of bone turnover increases risk of osteoporotic fracture later in life. The concentration of 25-hydroxyvitamin D that contributes to an elevated rate of bone turnover in older adults is unclear. The objective of this study was to investigate the associations between 25-hydroxyvitamin D and biochemical markers of bone turnover in an older, pan-European cohort. 25-hydroxyvitamin D and serum markers of bone-formation (osteocalcin and bone-specific alkaline phosphatase) were assessed by ELISA, while urinary markers of bone-resorption (pyridinoline and deoxypyridinoline) were assessed by HPLC. Six percent, 36 %, and 64 % of subjects had 25-hydroxyvitamin D concentrations < 25, < 50, and < 80 nmol/L throughout the year, respectively. 25-hydroxyvitamin D was significantly and inversely correlated with serum bone-specific alkaline phosphatase (r = 0.119; p = 0.022) and urinary pyridinoline (r = 0.207; p < 0.0001) and deoxypyridinoline (r = 0.230; p < 0.0001). Stratification on the basis of tertiles [T] of 25-hydroxyvitamin D (< 47.6 [T(1)]; 47.6 - 85.8 [T2]; > 85.8 [T3] nmol/L), showed that urinary pyridinoline and deoxypyridinoline were significantly lower in subjects in the 2(nd) and 3(rd) compared to the 1(st) tertile (p < 0.015). Low vitamin D status (< 50 nmol/L) was associated with an increased rate of bone turnover in this older pan-European cohort.


Assuntos
Envelhecimento/fisiologia , Biomarcadores/análise , Remodelação Óssea/fisiologia , Vitamina D/análogos & derivados , Idoso , Fosfatase Alcalina/sangue , Aminoácidos/urina , Estudos Transversais , Europa (Continente) , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Osteocalcina/sangue , Vitamina D/administração & dosagem , Vitamina D/sangue , Deficiência de Vitamina D/complicações
3.
J Endocrinol ; 202(1): 55-63, 2009 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-19398496

RESUMO

A reciprocal relationship between the endocrine and immune system has been demonstrated under pathophysiological conditions. However, few studies have assessed the relationship between thyroid hormones and immune function in apparently healthy individuals. Therefore, to clarify our understanding of normal physiological endocrine-immune interactions this study aimed to examine the interrelationships between thyroid hormones and immunity in healthy individuals. Total triiodothyronine (T(3)), total thyroxine (T(4)) and markers of immune status were assessed in 93 free-living and apparently healthy individuals aged 55-70 years. T(3) and T(4) concentrations were determined by commercially available kits. Immune status was assessed using flow cytometry and biochemical markers. Statistical analysis was performed by partial correlation, controlling for age. Thyroid hormone concentration was positively associated with markers of inflammation (P

Assuntos
Sistema Imunitário/fisiologia , Hormônios Tireóideos/fisiologia , Idoso , Biomarcadores/sangue , Estudos de Casos e Controles , Feminino , Saúde , Humanos , Sistema Imunitário/efeitos dos fármacos , Inflamação/sangue , Inflamação/imunologia , Masculino , Pessoa de Meia-Idade , Projetos Piloto , Hormônios Tireóideos/sangue , Hormônios Tireóideos/farmacologia
4.
J Am Coll Nutr ; 27(4): 463-9, 2008 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-18978165

RESUMO

OBJECTIVE: The aim of the study was to investigate whether zinc supplementation affects antioxidant status in European middle-aged and elderly people. DESIGN: Multicentre prospective intervention study, randomized, double-blind, placebo-control. SETTING: France (Clermont-Ferrand/Theix, and Grenoble), Italy (Rome), Northern Ireland (Coleraine). SUBJECTS: A total of 387 healthy middle-aged (55-70 yrs) and free-living older aged (70-85 yrs) subjects were randomly allocated to three groups: 0, 15 or 30 mg zinc gluconate/d in addition to usual dietary intake during 6 months. METHODS: Oxidative stress status was evaluated by measurement of protein oxidation (plasma thiol groups), lipid peroxidation (plasma thio-barbituric acid reactants, TBARS), whole blood glutathione levels, erythrocyte copper/zinc superoxide dismutase activity and plasma antioxidant status (ferric reducing antioxidant power assay), at baseline and after 3 and 6 months. RESULTS: Zinc supplementation did not alter oxidative stress markers and antioxidant defenses in elderly, after 3 or 6 months, except an increase in Cu/Zn superoxide dismutase activity. CONCLUSIONS: In apparently healthy free living elderly people, a single zinc supplementation had no effects on oxidative stress status.


Assuntos
Antioxidantes/farmacologia , Suplementos Nutricionais , Estresse Oxidativo/efeitos dos fármacos , Zinco/farmacologia , Idoso , Idoso de 80 Anos ou mais , Antioxidantes/metabolismo , Antioxidantes/uso terapêutico , Biomarcadores/metabolismo , Creatinina/urina , Método Duplo-Cego , Humanos , Isoprostanos/urina , Peroxidação de Lipídeos/efeitos dos fármacos , Pessoa de Meia-Idade , Superóxido Dismutase/metabolismo , Zinco/metabolismo , Zinco/uso terapêutico
5.
Clin Cancer Res ; 14(11): 3268-77, 2008 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-18519752

RESUMO

PURPOSE: The purpose of this study was to characterize the activity of the Bcl-2 protein family inhibitor ABT-263 in a panel of small cell lung cancer (SCLC) xenograft models. EXPERIMENTAL DESIGN: A panel of 11 SCLC xenograft models was established to evaluate the efficacy of ABT-263. Single agent activity was examined on a continuous dosing schedule in each of these models. The H146 model was used to further evaluate dose and schedule, comparison to standard cytotoxic agents, and induction of apoptosis. RESULTS: ABT-263 exhibited a range of antitumor activity, leading to complete tumor regression in several models. Significant regressions of tumors as large as 1 cc were also observed. The efficacy of ABT-263 was also quite durable; in several cases, minimal tumor regrowth was noted several weeks after the cessation of treatment. Antitumor effects were equal or superior to that of several clinically approved cytotoxic agents. Regression of large established tumors was observed through several cycles of therapy and efficacy was retained in a Pgp-1 overexpressing line. Significant efficacy was observed on several dose and therapeutic schedules and was associated with significant induction of apoptosis. CONCLUSIONS: ABT-263 is a potent, orally bioavailable inhibitor of Bcl-2 family proteins that has recently entered clinical trials. The efficacy data reported here suggest that SCLC is a promising area of clinical investigation with this agent.


Assuntos
Compostos de Anilina/administração & dosagem , Antineoplásicos/administração & dosagem , Carcinoma de Células Pequenas/tratamento farmacológico , Neoplasias Pulmonares/tratamento farmacológico , Sulfonamidas/administração & dosagem , Animais , Relação Dose-Resposta a Droga , Humanos , Camundongos , Camundongos Nus , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/efeitos dos fármacos , Ensaios Antitumorais Modelo de Xenoenxerto
6.
Biol Psychol ; 78(1): 1-9, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18243482

RESUMO

The aims of this study were to investigate the relationship between salivary cortisol, stress and mood and to look at the circadian rhythms of positive (PA) and negative (NA) mood in older adults. The participants were 41 healthy adults aged 55-69 years, recruited in Northern Ireland as part of the European Commission-funded Zenith project. Salivary cortisol samples were obtained twice a day (2.30 p.m. and 10.30 p.m.) for 7 consecutive days in conjunction with momentary measures of positive (PA) and negative mood (NA), using PANAS and a trait measure of perceived stress (Perceived Stress Scale). Salivary cortisol levels were measured using an enzyme-linked immunoassay kit. Higher perceived stress levels were associated with lower afternoon PA (r=-0.46, p=0.003) and higher afternoon (r=0.43, p=0.007) and evening (r=0.45, p=0.004) NA. Lower afternoon PA was correlated with higher evening cortisol concentrations (r=-0.47, p=0.002). Greater afternoon PA variability was associated with higher evening cortisol concentrations (r=0.38, p=0.015). A high intra-class correlation between cortisol and positive mood was found (r=0.67, p=0.009). Previously established rhythms for positive and negative mood were confirmed. Interestingly, there was no association between salivary cortisol levels and perceived stress in these healthy older adults. Further, more extensive research is required to better understand the apparent interplay between these variables and ageing.


Assuntos
Afeto/fisiologia , Ritmo Circadiano/fisiologia , Avaliação Geriátrica , Hidrocortisona/metabolismo , Saliva/metabolismo , Estresse Fisiológico/metabolismo , Idoso , Análise de Variância , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Escalas de Graduação Psiquiátrica , Fatores Sexuais
7.
Br J Nutr ; 99(1): 129-36, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17651517

RESUMO

Taste acuity declines with age and may be dependent upon Zn status. The aim of the present double-blind, randomised controlled intervention trial has been to determine taste acuity in response to Zn supplementation (placebo, or 15 or 30 mg Zn/d). Healthy older European adults aged 70-87 years were recruited within Italy (Rome) (n 108) and France (Grenoble) (n 91) to the European Commission-funded Zenith project. A signal detection theory approach was adopted for taste assessment. The data were converted to R indices and analysed by repeated-measures ANOVA controlling for baseline taste acuity as well as serum and erythrocyte Zn. Serum Zn increased post-intervention, indicating compliance with the intervention. Results differed across geographical region. Salt taste acuity was greater in response to Zn (30 mg) than placebo post-intervention among those recruited in Grenoble. There was no apparent change in acuity for sweet, sour or bitter taste in response to Zn. Supplemented Zn may have potential to enhance salt taste acuity in those over the age of 70 years. Further research is required to determine if enhanced salt taste acuity is reflected in the eating experiences of older individuals.


Assuntos
Cloreto de Sódio , Limiar Gustativo , Zinco/administração & dosagem , Idoso , Idoso de 80 Anos ou mais , Análise de Variância , Suplementos Nutricionais , Método Duplo-Cego , Eritrócitos/química , Feminino , França , Humanos , Masculino , Cidade de Roma , População Branca , Zinco/sangue
8.
J Gerontol A Biol Sci Med Sci ; 62(6): 598-608, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17595415

RESUMO

Aging is associated with alterations in the immune system, effects which may be exacerbated by inadequate zinc (Zn) status. We examined the relationship between Zn status and markers of immunity and the effect of supplementation with 15 mg or 30 mg Zn/d for 6 months on immune status in healthy individuals. Zn status was assessed by dietary intake and biochemical indices. Immune status was assessed by multiple flow cytometric methods. At baseline, Zn concentration was positively associated with lymphocyte subpopulation counts and T-lymphocyte activation. Zn supplementation of 30 mg/d significantly lowered B-lymphocyte count, albeit at month 3 only. Lower doses of Zn (15 mg Zn/d) significantly increased the ratio of CD4 to CD8 T lymphocytes at month 6. Overall, these findings suggest that total Zn intake (diet plus supplementation) of up to 40 mg Zn/d do not have significant long-term effects on immune status in apparently healthy persons aged 55-70 years.


Assuntos
Suplementos Nutricionais , Imunidade/efeitos dos fármacos , Oligoelementos/uso terapêutico , Zinco/uso terapêutico , Idoso , Linfócitos B/citologia , Biomarcadores/análise , Relação CD4-CD8 , Cobre/sangue , Método Duplo-Cego , Eritrócitos/metabolismo , Feminino , Citometria de Fluxo , Seguimentos , Humanos , Ferro/sangue , Ativação Linfocitária/imunologia , Contagem de Linfócitos , Subpopulações de Linfócitos/citologia , Masculino , Pessoa de Meia-Idade , Placebos , Linfócitos T/imunologia , Oligoelementos/sangue , Zinco/sangue
9.
Br J Nutr ; 97(3): 569-78, 2007 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-17313720

RESUMO

Given the key role of Zn in many physiological functions, optimal Zn status could be a predictive parameter of successful ageing. However, the benefit of Zn supplementation is still a matter of debate since Zn supplementation has been reported to be associated with the alteration of Cu status and lipid metabolism. As part of the Zenith Project, the present study aimed to investigate, in free-living healthy European middle-aged and older subjects, the effect of Zn supplementation on the biochemical status of Zn, Fe and Cu and on lipid profile. Volunteers aged 55-70 (n 188) and 70-85 (n 199) years old participated in a double-blinded, randomised study and received a daily placebo, or Zn as 15 or 30 mg for 6 months. Zn supplementation did not significantly modify erythrocyte Zn levels or erythrocyte Cu,Zn-superoxide dismutase activity. But Zn supplementation at 15 or 30 mg/d for 6 months increased significantly serum Zn levels and Zn urinary excretion with no major adverse effects on Fe and Cu status or on lipid metabolism. However, Zn supplementation at 30 mg/d showed some age- and sex-dependent alterations in Fe status or lipid profile. Therefore, with respect to the key role of an optimal Zn status in successful ageing, Zn supplementation at 15 mg/d, when necessary, could be safely proposed regarding lipids and the risk of interaction with Fe and Cu.


Assuntos
Suplementos Nutricionais , Metabolismo dos Lipídeos/efeitos dos fármacos , Oligoelementos/sangue , Zinco/farmacologia , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Cobre/administração & dosagem , Cobre/sangue , Relação Dose-Resposta a Droga , Método Duplo-Cego , Ingestão de Energia/efeitos dos fármacos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Zinco/farmacocinética
10.
Br J Nutr ; 96(4): 752-60, 2006 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17010236

RESUMO

A randomised double-blind placebo-controlled design was employed to investigate the effects of Zn supplementation on cognitive function in 387 healthy adults aged 55-87 years. Several measures of visual memory, working memory, attention and reaction time were obtained using the Cambridge Automated Neuropsychological Test Battery at baseline and then after 3 and 6 months of 0 (placebo), 15 or 30 mg Zn/d. Younger adults (< 70 years) performed significantly better on all tests than older adults (> 70 years), and performance improved with practice on some measures. For two out of eight dependent variables, there were significant interactions indicating a beneficial effect (at 3 months only) of both 15 and 30 mg/d on one measure of spatial working memory and a detrimental effect of 15 mg/d on one measure of attention. Further work is required to establish whether these findings generalise to older adults in poorer mental and physical health and with less adequate Zn intake and status than the present sample.


Assuntos
Cognição/efeitos dos fármacos , Suplementos Nutricionais , Zinco/farmacologia , Idoso , Idoso de 80 Anos ou mais , Envelhecimento/psicologia , Atenção/efeitos dos fármacos , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Masculino , Memória/efeitos dos fármacos , Pessoa de Meia-Idade , Testes Neuropsicológicos , Tempo de Reação/efeitos dos fármacos , Zinco/farmacocinética
12.
Cancer Res ; 66(17): 8731-9, 2006 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-16951189

RESUMO

Inhibition of the prosurvival members of the Bcl-2 family of proteins represents an attractive strategy for the treatment of cancer. We have previously reported the activity of ABT-737, a potent inhibitor of Bcl-2, Bcl-X(L), and Bcl-w, which exhibits monotherapy efficacy in xenograft models of small-cell lung cancer and lymphoma and potentiates the activity of numerous cytotoxic agents. Here we describe the biological activity of A-385358, a small molecule with relative selectivity for binding to Bcl-X(L) versus Bcl-2 (K(i)'s of 0.80 and 67 nmol/L for Bcl-X(L) and Bcl-2, respectively). This compound efficiently enters cells and co-localizes with the mitochondrial membrane. Although A-385358 shows relatively modest single-agent cytotoxic activity against most tumor cell lines, it has an EC(50) of <500 nmol/L in cells dependent on Bcl-X(L) for survival. In addition, A-385358 enhances the in vitro cytotoxic activity of numerous chemotherapeutic agents (paclitaxel, etoposide, cisplatin, and doxorubicin) in several tumor cell lines. In A549 non-small-cell lung cancer cells, A-385358 potentiates the activity of paclitaxel by as much as 25-fold. Importantly, A-385358 also potentiated the activity of paclitaxel in vivo. Significant inhibition of tumor growth was observed when A-385358 was added to maximally tolerated or half maximally tolerated doses of paclitaxel in the A549 xenograft model. In tumors, the combination therapy also resulted in a significant increase in mitotic arrest followed by apoptosis relative to paclitaxel monotherapy.


Assuntos
Compostos de Anilina/farmacologia , Antineoplásicos/uso terapêutico , Compostos de Bifenilo/uso terapêutico , Neoplasias Pulmonares/tratamento farmacológico , Nitrofenóis/uso terapêutico , Sulfonamidas/farmacologia , Sulfonamidas/uso terapêutico , Proteína bcl-X/antagonistas & inibidores , Compostos de Anilina/farmacocinética , Compostos de Anilina/uso terapêutico , Animais , Antineoplásicos/farmacocinética , Antineoplásicos/farmacologia , Compostos de Bifenilo/farmacocinética , Compostos de Bifenilo/farmacologia , Linhagem Celular Tumoral , Sinergismo Farmacológico , Humanos , Cinética , Masculino , Camundongos , Camundongos SCID , Nitrofenóis/farmacocinética , Nitrofenóis/farmacologia , Paclitaxel/farmacocinética , Piperazinas/farmacocinética , Piperazinas/farmacologia , Piperazinas/uso terapêutico , Sulfonamidas/farmacocinética , Transplante Heterólogo
13.
Br J Nutr ; 95(6): 1134-42, 2006 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-16768836

RESUMO

Zn has been shown to possess antioxidant properties in vitro and in vivo. As inadequate dietary Zn intake has been reported in these populations, Zn supplementation may protect against oxidative stress and thereby limit the progression of degenerative diseases in such populations. We conducted the present study to evaluate the long-term supplementation effects of two moderate doses of Zn on in vitro Cu-induced LDL oxidation in French men and women. Three groups of sixteen healthy subjects aged 55-70 years from each sex participated in this randomized double-blind, placebo-controlled study. Each group received for six months either 0, 15 or 30 mg supplemental Zn per d. At the beginning and at the end of the supplementation periods, dietary intakes of Zn, Cu, Fe and vitamin E were estimated using 4 d food-intake records (including the weekend) and the GENI program. Zn, Cu, Fe and vitamin E status were also determined. In vitro LDL oxidizability (basal conjugated diene level, maximal conjugated diene formation and lag time) and lipid parameters were also determined. Dietary intakes of Zn, Cu, Fe and vitamin E were adequate in this population. Zn supplementation significantly increased serum Zn levels but did not significantly modify Cu, Fe or vitamin E status. However, Zn supplementation had no effect on in vitro LDL oxidation parameters, nor were there any sex-related differences in in vitro LDL oxidizability. The present study showed that long-term Zn supplementation of healthy subjects aged 55-70 years had no effect on in vitro Cu-induced LDL oxidation under the study conditions.


Assuntos
Cobre/administração & dosagem , Dieta , Lipoproteínas LDL/metabolismo , Zinco/administração & dosagem , Idoso , Análise de Variância , Colesterol/sangue , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Cobre/sangue , Cobre/urina , Suplementos Nutricionais , Método Duplo-Cego , Esquema de Medicação , Feminino , Humanos , Ferro/administração & dosagem , Ferro/metabolismo , Masculino , Pessoa de Meia-Idade , Oxirredução , Falha de Tratamento , Vitamina E/administração & dosagem , Vitamina E/metabolismo , Vitaminas/administração & dosagem , Vitaminas/metabolismo , Zinco/sangue , Zinco/urina
14.
Br J Nutr ; 94(2): 231-6, 2005 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16115357

RESUMO

Western diets containing suboptimal Cu concentrations could be widespread. A link between marginal Cu deficiency and CVD has been suggested. The objective of the present study was to investigate the effect of Cu supplementation on both Cu status and CVD risk factors in healthy young women. Sixteen women with a mean age of 24 (sd 2) years participated in a randomised crossover study of three 4-week periods with 3-week washouts between periods. During each intervention period, subjects received 0, 3 or 6 mg elemental Cu/d as CuSO4 in addition to their habitual diet. Blood samples were taken to assess the effect of supplementation on putative markers of Cu status. The content of plasma lipids, lipoprotein (a), apo and certain haemostatic factors, as putative indices of CVD, was also analysed. Daily supplementation with 3 mg Cu significantly increased (P < 0.05) serum Cu concentration and the activity of erythrocyte superoxide dismutase, although there was no further significant increase after an intake of 6 mg Cu/d. The concentration of the fibrinolytic factor plasminogen activator inhibitor type 1 was significantly reduced (P < 0.05) by about 30 % after supplementation with 6 mg Cu/d. No other marker of Cu status or CVD risk factor was affected by Cu supplementation. The results indicate that supplementation with 3 or 6 mg Cu/d may improve Cu status in these healthy young women. Increased Cu intake could reduce the risk of CVD and atherosclerosis in man by promoting improved fibrinolytic capacity.


Assuntos
Doenças Cardiovasculares/etiologia , Cobre/administração & dosagem , Suplementos Nutricionais , Adulto , Fatores de Coagulação Sanguínea/análise , Proteína C-Reativa/análise , Colesterol/sangue , Cobre/sangue , Estudos Cross-Over , Método Duplo-Cego , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Eritrócitos/enzimologia , Feminino , Humanos , Leucócitos/enzimologia , Fatores de Risco , Superóxido Dismutase/metabolismo , Triglicerídeos/sangue
15.
Nature ; 435(7042): 677-81, 2005 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-15902208

RESUMO

Proteins in the Bcl-2 family are central regulators of programmed cell death, and members that inhibit apoptosis, such as Bcl-X(L) and Bcl-2, are overexpressed in many cancers and contribute to tumour initiation, progression and resistance to therapy. Bcl-X(L) expression correlates with chemo-resistance of tumour cell lines, and reductions in Bcl-2 increase sensitivity to anticancer drugs and enhance in vivo survival. The development of inhibitors of these proteins as potential anti-cancer therapeutics has been previously explored, but obtaining potent small-molecule inhibitors has proved difficult owing to the necessity of targeting a protein-protein interaction. Here, using nuclear magnetic resonance (NMR)-based screening, parallel synthesis and structure-based design, we have discovered ABT-737, a small-molecule inhibitor of the anti-apoptotic proteins Bcl-2, Bcl-X(L) and Bcl-w, with an affinity two to three orders of magnitude more potent than previously reported compounds. Mechanistic studies reveal that ABT-737 does not directly initiate the apoptotic process, but enhances the effects of death signals, displaying synergistic cytotoxicity with chemotherapeutics and radiation. ABT-737 exhibits single-agent-mechanism-based killing of cells from lymphoma and small-cell lung carcinoma lines, as well as primary patient-derived cells, and in animal models, ABT-737 improves survival, causes regression of established tumours, and produces cures in a high percentage of the mice.


Assuntos
Antineoplásicos/uso terapêutico , Compostos de Bifenilo/farmacologia , Compostos de Bifenilo/uso terapêutico , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Proteínas Proto-Oncogênicas c-bcl-2/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-bcl-2/classificação , Animais , Antineoplásicos/síntese química , Antineoplásicos/química , Antineoplásicos/farmacologia , Apoptose/efeitos dos fármacos , Compostos de Bifenilo/síntese química , Compostos de Bifenilo/química , Carcinoma de Células Pequenas/tratamento farmacológico , Carcinoma de Células Pequenas/patologia , Linhagem Celular Tumoral , Citocromos c/metabolismo , Modelos Animais de Doenças , Sinergismo Farmacológico , Humanos , Linfoma/tratamento farmacológico , Linfoma/patologia , Espectroscopia de Ressonância Magnética , Camundongos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Modelos Moleculares , Nitrofenóis , Paclitaxel/farmacologia , Piperazinas , Proteínas Proto-Oncogênicas c-bcl-2/metabolismo , Relação Estrutura-Atividade , Sulfonamidas , Taxa de Sobrevida
16.
Biol Trace Elem Res ; 93(1-3): 75-86, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-12835492

RESUMO

Pharmacological doses of zinc can adversely affect body copper status. The resulting copper deficiency can impact directly upon cholesterol metabolism and a suboptimal copper status has been observed to influence markers of hemostasis (specifically fibrinogen and the copper-containing coagulation factors V and VIII). The aim of this investigation was to examine the effect of a low level of zinc supplementation, to include dietary intake, at the United States tolerable upper intake level of 40 mg/d upon indicators of lipid metabolism, hemostasis, and copper. Thirty-eight subjects were recruited onto a double-blind placebo-controlled intervention trial and randomly selected to one of two groups. Group 1 took zinc supplements (30 mg/d) for 14 wk followed by copper supplements (3 mg/d) for 8 wk (to counteract adverse effects, if any, of zinc supplementation). A second group took placebo supplements for the full duration of the trial. Estimated dietary zinc intake approximated 10 mg/d. The effect of supplement was analyzed by repeated-measures analysis of variance (anova). Results indicate that no effect of zinc supplementation on putative indices of copper status, lipoprotein metabolism, and markers of hemostasis. These results indicate that short-term low-level zinc supplementation (total intake 40 mg/d) is not detrimental to health.


Assuntos
Cobre/metabolismo , Suplementos Nutricionais , Saúde , Hemostasia/efeitos dos fármacos , Lipoproteínas/metabolismo , Zinco/farmacologia , Adulto , Cobre/sangue , Suplementos Nutricionais/efeitos adversos , Método Duplo-Cego , Comportamento Alimentar , Humanos , Lipoproteínas/sangue , Masculino , Pessoa de Meia-Idade , Nível de Efeito Adverso não Observado , Inquéritos e Questionários , Zinco/administração & dosagem , Zinco/efeitos adversos
17.
Br J Nutr ; 89(5): 695-703, 2003 May.
Artigo em Inglês | MEDLINE | ID: mdl-12720590

RESUMO

As a result of evidence documenting harmful effects of Zn supplementation on immune function and Cu status, thirty-eight men were recruited onto a Zn supplementation trial. The aim was to examine the effects of chronic Zn supplementation on circulating levels of peripheral blood leucocytes and lymphocyte subsets. Subjects (n 19) took 30 mg Zn/d for 14 weeks followed by 3 mg Cu/d for 8 weeks to counteract adverse effects, if any, of Zn supplementation on immune status resulting from lowered Cu status. A control group (n 19) took placebo supplements for the duration of the trial. Dietary intakes of Zn approximated 10 mg/d. Blood samples, taken throughout the trial, were assessed for full blood profiles and flow cytometric analyses of lymphocyte subsets. Putative indices of Cu status were also examined. Results indicate that there was no effect of Zn supplementation on circulating levels of peripheral blood leucocytes or on lymphocyte subsets. Cu status was also unaltered. Independent of supplement, there appeared to be seasonal variations in selected lymphocyte subsets in both placebo and supplemented groups. Alterations in circulating levels of B cells (cluster of differentiation (CD) 19), memory T cells (CD45RO) and expression of the intracellular adhesion molecule-1 (CD54) on T cells were observed. Findings indicated no adverse effects of Zn supplementation on immune status or Cu status and support the US upper level of Zn tolerance of 40 mg/d. The seasonal variations observed in lymphocyte subsets in the group as a whole could have implications for seasonal variability in the incidence of infectious diseases.


Assuntos
Suplementos Nutricionais , Subpopulações de Linfócitos/efeitos dos fármacos , Zinco/efeitos adversos , Adulto , Análise de Variância , Ceruloplasmina/análise , Cobre/administração & dosagem , Cobre/sangue , Método Duplo-Cego , Citometria de Fluxo , Humanos , Contagem de Leucócitos , Subpopulações de Linfócitos/imunologia , Masculino , Nível de Efeito Adverso não Observado , Estações do Ano , Superóxido Dismutase/sangue , Zinco/administração & dosagem , Zinco/sangue
18.
Br J Nutr ; 87(5): 393-403, 2002 May.
Artigo em Inglês | MEDLINE | ID: mdl-12010579

RESUMO

Cu appears to have many important functional roles in the body that apparently relate, among others, to the maintenance of immune function, bone health and haemostasis. Some have suggested a role for long-term marginal Cu deficiency in the aetiology of a number of degenerative diseases. Accurate diagnosis of marginal Cu deficiency, however, has remained elusive despite an increased understanding of the biochemistry of Cu and its physiological roles in the body. Traditional markers of Cu status, such as serum Cu and caeruloplasmin protein concentrations are insensitive to subtle changes in Cu status. Cu-containing enzymes, such as Cu-Zn-superoxide dismutase, cytochrome c oxidase and diamine oxidase, may be more reliable but evidence to date is not conclusive. Development of markers sensitive to marginal Cu status is essential before conclusions can be drawn concerning the risks of long-term intake of suboptimal dietary Cu. As Cu appears to be essential for maintenance of immune function, activities of specific immunological markers, altered in Cu deficiency, offer alternatives. This review evaluates a selection of immunological markers that could be considered potentially sensitive markers of marginal Cu status. The indices of immune function reviewed are neutrophil function, interleukin 2 production, blastogenic response to mitogens and lymphocyte subset phenotyping.


Assuntos
Cobre/deficiência , Sistema Imunitário/fisiologia , Biomarcadores/análise , Cobre/imunologia , Humanos , Estado Nutricional
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