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1.
J Alzheimers Dis ; 70(s1): S221-S237, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30475762

RESUMO

BACKGROUND: Maintain Your Brain (MYB) is a randomized controlled trial of an online multi-modal lifestyle intervention targeting modifiable dementia risk factors with its primary aim being to reduce cognitive decline in an older age cohort. METHODS: MYB aims to recruit 8,500 non-demented community dwelling 55 to 77 year olds from the Sax Institute's 45 and Up Study in New South Wales, Australia. Participants will be screened for risk factors related to four modules that comprise the MYB intervention: physical activity, nutrition, mental health, and cognitive training. Targeting risk factors will enable interventions to be personalized so that participants receive the most appropriate modules. MYB will run for three years and up to four modules will be delivered sequentially each quarter during year one. Upon completing a module, participants will continue to receive less frequent booster activities for their eligible modules (except for the mental health module) until the end of the trial. DISCUSSION: MYB will be the largest internet-based trial to attempt to prevent cognitive decline and potentially dementia. If successful, MYB will provide a model for not just effective intervention among older adults, but an intervention that is scalable for broad use.


Assuntos
Disfunção Cognitiva/prevenção & controle , Exercício Físico , Promoção da Saúde , Estilo de Vida , Idoso , Feminino , Humanos , Vida Independente , Masculino , Saúde Mental , Pessoa de Meia-Idade , Qualidade de Vida , Ensaios Clínicos Controlados Aleatórios como Assunto , Fatores de Risco , Comportamento de Redução do Risco
2.
Cancer Prev Res (Phila) ; 7(8): 786-95, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25092886

RESUMO

High red meat (HRM) intake is associated with increased colorectal cancer risk, while resistant starch is probably protective. Resistant starch fermentation produces butyrate, which can alter microRNA (miRNA) levels in colorectal cancer cells in vitro; effects of red meat and resistant starch on miRNA expression in vivo were unknown. This study examined whether a HRM diet altered miRNA expression in rectal mucosa tissue of healthy volunteers, and if supplementation with butyrylated resistant starch (HRM+HAMSB) modified this response. In a randomized cross-over design, 23 volunteers undertook four 4-week dietary interventions; an HRM diet (300 g/day lean red meat) and an HRM+HAMSB diet (HRM with 40 g/day butyrylated high amylose maize starch), preceded by an entry diet and separated by a washout. Fecal butyrate increased with the HRM+HAMSB diet. Levels of oncogenic mature miRNAs, including miR17-92 cluster miRNAs and miR21, increased in the rectal mucosa with the HRM diet, whereas the HRM+HAMSB diet restored miR17-92 miRNAs, but not miR21, to baseline levels. Elevated miR17-92 and miR21 in the HRM diet corresponded with increased cell proliferation, and a decrease in miR17-92 target gene transcript levels, including CDKN1A. The oncogenic miR17-92 cluster is differentially regulated by dietary factors that increase or decrease risk for colorectal cancer, and this may explain, at least in part, the respective risk profiles of HRM and resistant starch. These findings support increased resistant starch consumption as a means of reducing risk associated with an HRM diet.


Assuntos
Dieta , Regulação Neoplásica da Expressão Gênica , Mucosa Intestinal/metabolismo , Intestinos/microbiologia , MicroRNAs/metabolismo , Neoplasias Retais/metabolismo , Idoso , Amilose/química , Animais , Bebidas , Biópsia , Proliferação de Células , Citrus , Análise por Conglomerados , Estudos Cross-Over , Feminino , Perfilação da Expressão Gênica , Humanos , Masculino , Carne , Pessoa de Meia-Idade , Leite , Família Multigênica , RNA Longo não Codificante , Amido , Zea mays
3.
Age Ageing ; 43(6): 857-62, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25049262

RESUMO

BACKGROUND: accurate and practical assessment methods for assessing appendicular skeletal muscle (ASM) is of clinical importance for the diagnosis of geriatric syndromes associated with skeletal muscle wasting. OBJECTIVES: the purpose of this study was to develop and cross-validate novel anthropometric prediction equations for the estimate of ASM in older adults post-surgical fixation for hip fracture, using dual-energy X-ray absorptiometry (DEXA) as the criterion measure. SUBJECTS: community-dwelling older adults (aged ≥65 years) recently hospitalised for hip fracture. SETTING: participants were recruited from hospital in the acute phase of recovery. DESIGN: validation measurement study. MEASUREMENTS: a total of 79 hip fracture patients were involved in the development of the regression models (MD group). A further 64 hip fracture patients also recruited in the early phase of recovery were used in the cross-validation of the regression models (CV group). Multiple linear regression analyses were undertaken in the MD group to identify the best performing prediction models. The linear coefficient of determination (R(2)) in addition to the standard error of the estimate (SEE) were calculated to determine the best performing model. Agreement between estimated ASM and ASMDEXA in the CV group was assessed using paired t-tests with the 95% limits of agreement (LOA) assessed using Bland-Altman analyses. RESULTS: the mean age of all the participants was 82.1 ± 7.3 years. The best two prediction models are presented as follows: ASMPRED-EQUATION_1: 22.28 - (0.069 * age) + (0.407 * weight) - (0.807 * BMI) - (0.222 * MAC) (adjusted R(2): 0.76; SEE: 1.80 kg); ASMPRED-EQUATION_2: 16.77 - (0.036 * age) + (0.385 * weight) - (0.873 * BMI) (adjusted R(2): 0.73; SEE: 1.90 kg). The mean bias from the CV group between ASMDEXA and the predictive equations is as follows: ASMDEXA - ASMPRED-EQUATION_1: 0.29 ± 2.6 kg (LOA: -4.80, 5.40 kg); ASMDEXA - ASMPRED-EQUATION_2: 0.13 ± 2.5 kg (LOA: -4.77, 5.0 kg). No significant difference was observed between measured ASMDEXA and estimated ASM (ASMDEXA: 16.4 ± 3.9 kg; ASMPRED-EQUATION_1: 16.7 ± 3.2 kg (P = 0.379); ASMPRED-EQUATION_2: 16.6 ± 3.2 kg (P = 0.670)). CONCLUSIONS: we have developed and cross-validated novel anthropometric prediction equations against DEXA for the estimate of ASM designed for application in older orthopaedic patients. Our equation may be of use as an alternative to DEXA in the diagnosis of skeletal muscle wasting syndromes. Further validation studies are required to determine the clinical utility of our equation across other settings, including hip fracture patients admitted from residential care, and also with a longer-term follow-up.


Assuntos
Absorciometria de Fóton , Antropometria/métodos , Composição Corporal , Fraturas do Quadril/diagnóstico , Modelos Biológicos , Músculo Esquelético/diagnóstico por imagem , Músculo Esquelético/fisiopatologia , Atrofia Muscular/diagnóstico , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Peso Corporal , Feminino , Fixação de Fratura , Fraturas do Quadril/diagnóstico por imagem , Fraturas do Quadril/fisiopatologia , Fraturas do Quadril/cirurgia , Hospitalização , Humanos , Modelos Lineares , Masculino , Atrofia Muscular/diagnóstico por imagem , Atrofia Muscular/fisiopatologia , Valor Preditivo dos Testes , Ensaios Clínicos Controlados Aleatórios como Assunto , Recuperação de Função Fisiológica , Reprodutibilidade dos Testes , Fatores de Tempo , Resultado do Tratamento
4.
Trends Mol Med ; 20(9): 479-86, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24801560

RESUMO

Genome sequencing has the potential for stratified cancer treatment and improved diagnostics for rare disorders. However, sequencing needs to be utilised in risk stratification on a population scale to deepen the impact on the health system by addressing common diseases, where individual genomic variants have variable penetrance and minor impact. As the accuracy of genomic risk predictors is bounded by heritability, environmental factors such as diet, lifestyle, and microbiome have to be considered. Large-scale, longitudinal research programmes need to study the intrinsic properties between both genetics and environment to unravel their risk contribution. During this discovery process, frameworks need to be established to counteract unrealistic expectations. Sufficient scientific evidence is needed to interpret sources of uncertainty and inform decision making for clinical management and personal health.


Assuntos
Atenção à Saúde/métodos , Genômica/métodos , Medicina de Precisão , Registros Eletrônicos de Saúde , Genômica/tendências , Humanos , Avaliação Nutricional , Fatores de Risco
6.
BMC Geriatr ; 13: 41, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23634646

RESUMO

BACKGROUND: Omega-3 (n-3) fatty acid supplementation is becoming increasingly popular. However given its antithrombotic properties the potential for severe adverse events (SAE) such as bleeding has safety implications, particularly in an older adult population. A systematic review of randomized control trials (RCT) was conducted to explore the potential for SAE and non-severe adverse events (non-SAE) associated with n-3 supplementation in older adults. METHODS: A comprehensive search strategy using Medline and a variety of other electronic sources was conducted. Studies investigating the oral administration of n-3 fish oil containing eicosapentaenoic acid (EPA), docosahexaenoic acid (DHA) or both against a placebo were sourced. The primary outcome of interest included reported SAE associated with n-3 supplementation. Chi-square analyses were conducted on the pooled aggregate of AEs. RESULTS: Of the 398 citations initially retrieved, a total of 10 studies involving 994 older adults aged ≥60 years were included in the review. Daily fish oil doses ranged from 0.03 g to 1.86 g EPA and/or DHA with study durations ranging from 6 to 52 weeks. No SAE were reported and there were no significant differences in the total AE rate between groups (n-3 intervention group: 53/540; 9.8%; placebo group: 28/454; 6.2%; p = 0.07). Non-SAE relating to gastrointestinal (GI) disturbances were the most commonly reported however there was no significant increase in the proportion of GI disturbances reported in participants randomized to the n-3 intervention (n-3 intervention group: 42/540 (7.8%); placebo group: 24/454 (5.3%); p = 0.18). CONCLUSIONS: The potential for AEs appear mild-moderate at worst and are unlikely to be of clinical significance. The use of n-3 fatty acids and the potential for SAE should however be further researched to investigate whether this evidence is consistent at higher doses and in other populations. These results also highlight that well-documented data outlining the potential for SAE following n-3 supplementation are limited nor adequately reported to draw definitive conclusions concerning the safety associated with n-3 supplementation. A more rigorous and systematic approach for monitoring and recording AE data in clinical settings that involve n-3 supplementation is required.


Assuntos
Suplementos Nutricionais/efeitos adversos , Óleos de Peixe/efeitos adversos , Idoso , Idoso de 80 Anos ou mais , Relação Dose-Resposta a Droga , Ácidos Graxos Ômega-3/administração & dosagem , Ácidos Graxos Ômega-3/efeitos adversos , Óleos de Peixe/administração & dosagem , Gastroenteropatias/induzido quimicamente , Gastroenteropatias/epidemiologia , Humanos , Pessoa de Meia-Idade , Ensaios Clínicos Controlados Aleatórios como Assunto
7.
Mol Carcinog ; 52(6): 459-74, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22308110

RESUMO

Diet-derived butyrate, a histone deacetylase inhibitor (HDI), decreases proliferation and increases apoptosis in colorectal cancer (CRC) cells via epigenetic changes in gene expression. Other HDIs such as suberoylanilide hydroxamic acid (SAHA) and trichostatin A (TSA) have similar effects. This study examined the role of microRNAs (miRNAs) in mediating the chemo-protective effects of HDIs, and explored functions of the oncogenic miR-17-92 cluster. The dysregulated miRNA expression observed in HT29 and HCT116 CRC cells could be epigenetically altered by butyrate, SAHA and TSA. These HDIs decreased expression of miR-17-92 cluster miRNAs (P < 0.05), with a corresponding increase in miR-17-92 target genes, including PTEN, BCL2L11, and CDKN1A (P < 0.05). The decrease in miR-17-92 expression may be partly responsible for the anti-proliferative effects of HDIs, with introduction of miR-17-92 cluster miRNA mimics reversing this effect and decreasing levels of PTEN, BCL2L11, and CDKN1A (P < 0.05). The growth effects of HDIs may be mediated by changes in miRNA activity, with down-regulation of the miR-17-92 cluster a plausible mechanism to explain some of the chemo-protective effects of HDIs. Of the miR-17-92 cluster miRNAs, miR-19a and miR-19b were primarily responsible for promoting proliferation, while miR-18a acted in opposition to other cluster members to decrease growth. NEDD9 and CDK19 were identified as novel miR-18a targets and were shown to be pro-proliferative genes, with RNA interference of their transcripts decreasing proliferation in CRC cells. This is the first study to identify competing roles for miR-17-92 cluster members, in the context of HDI-induced changes in CRC cells.


Assuntos
Adenocarcinoma/tratamento farmacológico , Ácido Butírico/farmacologia , Neoplasias Colorretais/tratamento farmacológico , Inibidores de Histona Desacetilases/farmacologia , Ácidos Hidroxâmicos/farmacologia , MicroRNAs/genética , Proteínas Adaptadoras de Transdução de Sinal/genética , Adenocarcinoma/genética , Proteínas Reguladoras de Apoptose/genética , Proteína 11 Semelhante a Bcl-2 , Neoplasias Colorretais/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Regulação para Baixo/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Células HCT116 , Células HT29 , Humanos , Proteínas de Membrana/genética , PTEN Fosfo-Hidrolase/genética , Fosfoproteínas/genética , Proteínas Proto-Oncogênicas/genética , RNA Longo não Codificante , RNA Mensageiro/genética , Transfecção , Vorinostat
8.
Asia Pac J Clin Nutr ; 21(3): 386-93, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22705428

RESUMO

Nutritional status is often impaired in ambulatory rehabilitation patients. Wasting conditions can be classified as starvation, sarcopenia or cachexia but differences between these are not well defined, and misdiagnosis may lead to inappropriate intervention. A secondary analysis of data from 187 ambulatory rehabilitation patients aged >=60 years aimed to identify patients with one or more wasting condition, and investigate the impact on common rehabilitation outcomes. Starvation was defined by fat-free mass index and the Council on Nutrition Appetite Questionnaire score; sarcopenia by fat-free mass index and quadriceps strength; and cachexia by fat-free mass index and serum C-reactive protein. Selected rehabilitation outcomes were compared for those who were, and those who were not, identified as having one or more wasting condition. Of those identified with starvation (n=30), all were also identified as sarcopenic and 20 as cachectic; of those identified as sarcopenic (n=75), 30 had starvation and 37 were cachectic; and of those identified as cachectic (n=37), 20 had starvation and all were sarcopenic. Twenty participants were identified as having all three conditions. Those with starvation had higher level of depression (p=0.003), lower self-rated health (p=0.032), and lower levels of physical function (motor p=0.006; process p=0.004) than those with no evidence of a wasting condition. Those who had sarcopenia had lower physical function (motor p=0.012; process p=0.003) as did those with cachexia (motor p=0.025; process p=0.042). Results suggest problems in operationalising definitions in an ambulatory clinical setting. The overlap identified in this analysis suggests that up to 40% (75/187) of patients could be misidentified and prescribed inappropriate nutritional support.


Assuntos
Caquexia/fisiopatologia , Sarcopenia/fisiopatologia , Inanição/fisiopatologia , Síndrome de Emaciação/etiologia , Idoso , Idoso de 80 Anos ou mais , Instituições de Assistência Ambulatorial , Atitude Frente a Saúde , Composição Corporal , Índice de Massa Corporal , Proteína C-Reativa/análise , Caquexia/sangue , Caquexia/complicações , Caquexia/diagnóstico , Estudos Transversais , Depressão/complicações , Depressão/epidemiologia , Diagnóstico Diferencial , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Força Muscular , Músculo Quadríceps/fisiopatologia , Centros de Reabilitação , Sarcopenia/sangue , Sarcopenia/complicações , Sarcopenia/diagnóstico , Austrália do Sul/epidemiologia , Inanição/sangue , Inanição/complicações , Inanição/diagnóstico , Síndrome de Emaciação/psicologia
9.
Carcinogenesis ; 33(1): 197-202, 2012 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-22080572

RESUMO

Animal studies show that increasing large bowel butyrate concentration through ingestion of butyrylated or resistant starches opposes carcinogen-induced tumorigenesis, which is consistent with population data linking greater fiber consumption with lowered colorectal cancer (CRC) risk. Butyrate has been shown to regulate the apoptotic response to DNA damage. This study examined the impact of increasing large bowel butyrate concentration by dietary butyrylated starch on the colonic epithelium of rats treated with the genotoxic carcinogen azoxymethane (AOM). Four groups of 10 male rats were fed AIN-93G based-diets containing either low amylose maize starch (LAMS), LAMS with 3% tributyrin, 10% high amylose maize starch (HAMS) or 10% butyrylated HAMS (HAMSB). HAMS and HAMSB starches were cooked by heating in water. After 4 weeks, rats were injected once with AOM and killed 6 h later. Rates of apoptosis and proliferation were measured in colonic epithelium. Short-chain fatty acid concentrations in large bowel digesta and hepatic portal venous plasma were higher in HAMSB than all other groups. Apoptotic rates in the distal colon were increased by HAMSB and correlated with luminal butyrate concentrations but cellular proliferation rates were unaffected by diet. The increase in apoptosis was most marked in the base and proliferative zone of the crypt. Regulation of luminal butyrate using HAMSB increases the rates of apoptotic deletion of DNA-damaged colonocytes. We propose this pro-apoptotic function of butyrate plays a major role reducing tumour formation in the AOM-treated rat and that these data support a potential protective role of butyrate in CRC.


Assuntos
Apoptose/efeitos dos fármacos , Butiratos/farmacologia , Neoplasias do Colo/prevenção & controle , Amido/farmacologia , Animais , Azoximetano , Caspase 3/fisiologia , Proliferação de Células/efeitos dos fármacos , Neoplasias do Colo/induzido quimicamente , Neoplasias do Colo/patologia , Ácidos Graxos Voláteis/sangue , Mucosa Intestinal/patologia , Masculino , Ratos , Ratos Sprague-Dawley
10.
Asia Pac J Clin Nutr ; 20(2): 175-9, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21669585

RESUMO

Inflammatory conditions likely to benefit from fish oil therapy are prevalent in older adults however acceptability in this group is uncertain. This study aimed to assess the palatability of a range of liquid fish oil concentrations, the frequency and extent of side effects, and to summarise any effects on adherence to fish oil therapy in older adults. One hundred patients (>=60 years) completed a randomised, single-blind palatability study, conducted in two parts. In part one, 50 subjects, blinded to random sample order, consumed multiple liquid fish oil samples (2x10%, 40% and 100%). In part two, 50 subjects tasted one concentration, or 100% extra light olive oil (control). Pleasantness of taste was scored on a 5-point Likert scale. Side effects were recorded 24-hr post-tasting. Results of part one showed that 9/50 participants reported increasingly unpleasant taste with increasing fish oil concentration. 14/50 reported unpleasant taste for 100% fish oil vs 7/50 for 10%. 14/50 reported side effects which would not affect compliance with therapy. For part two, 1/12 reported unpleasant taste for 100% vs 0/13 for 10% fish oil or control. 4/50 reported side effects and 2/4 indicated these would prevent ongoing fish oil therapy. The authors conclude that taste itself is not a deterrent to fish oil therapy. Furthermore, reported adverse effects may not be a true reaction to fish oil, or dissuade patients from compliance. Liquid fish oil supplements are acceptable to older adults, therefore should be investigated as a therapy for geriatric conditions.


Assuntos
Suplementos Nutricionais , Óleos de Peixe/administração & dosagem , Cooperação do Paciente/estatística & dados numéricos , Satisfação do Paciente/estatística & dados numéricos , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Azeite de Oliva , Óleos de Plantas/administração & dosagem , Método Simples-Cego , Estatísticas não Paramétricas , Paladar
11.
BMC Geriatr ; 10: 76, 2010 Oct 22.
Artigo em Inglês | MEDLINE | ID: mdl-20964865

RESUMO

BACKGROUND: Proximal femoral fractures are associated with increased morbidity and mortality. Pre-existing malnutrition and weight loss amongst this patient group is of primary concern, with conventional nutrition support being largely ineffective. The inflammatory response post proximal femoral fracture surgery and the subsequent risk of cachexia may explain the inability of conventional high energy high protein management to produce an anabolic response amongst these patients. Omega-3 fatty acids derived from fish oils have been extensively studied for their anti-inflammatory benefits. Due to their anti-inflammatory properties, the benefit of fish oil combined with individualized nutrition support amongst proximal femoral fracture patients post surgery is an attractive potential therapeutic strategy. The aim of the ATLANTIC trial is to assess the potential benefits of an anti-inflammatory dose of fish oil within the context of a 12 week individualised nutrition program, commencing seven days post proximal femoral fracture surgery. METHODS/DESIGN: This randomized controlled, double blinded trial, will recruit 150 community dwelling elderly patients aged ≥65 years, within seven days of surgery for proximal femoral fracture. Participants will be randomly allocated to receive either a 12 week individualized nutrition support program complemented with 20 ml/day anti-inflammatory dose fish oil (~3.6 g eicosapentaenoic acid, ~2.4 g docosahexanoic acid; intervention), or, a 12 week individualized nutrition support program complemented with 20 ml/day low dose fish oil (~0.36 g eicosapentaenoic acid, ~0.24 g docosahexanoic acid; control). DISCUSSION: The ATLANTIC trial is the first of its kind to provide fish oil combined with individualized nutrition therapy as an intervention to address the inflammatory response experienced post proximal femoral fracture surgery amongst elderly patients. The final outcomes of this trial will assist clinicians in the development of effective and alternative treatment methods post proximal femoral fracture surgery which may ultimately result in a reduction in systemic inflammation, loss of weight and lean muscle and improvements in nutritional status, mobility, independence and quality of life among elderly patients. TRIAL REGISTRATION: ACTRN12609000241235.


Assuntos
Caquexia/dietoterapia , Ácidos Graxos Ômega-3/administração & dosagem , Óleos de Peixe/administração & dosagem , Fraturas do Quadril/dietoterapia , Idoso , Idoso de 80 Anos ou mais , Caquexia/etiologia , Caquexia/prevenção & controle , Método Duplo-Cego , Fraturas do Quadril/complicações , Humanos , Estado Nutricional/fisiologia , Resultado do Tratamento
12.
Nutr Res ; 30(6): 427-34, 2010 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-20650351

RESUMO

The short-chain fatty acids acetate, propionate, and butyrate are produced by colonic bacterial fermentation of carbohydrates. Butyrate is important in the regulation of the colonocyte cell cycle and gut motility and may also reduce the risk of large bowel cancer. We have shown that dietary butyrylated starch can deliver butyrate to the large bowel in a sustained manner. We hypothesized that ingestion of butyrylated starch increases large bowel butyrate levels and decreases colonic contractility. Groups of male Sprague-Dawley rats (n = 8) were fed AIN-93G-based diet containing a highly digestible low-amylose maize starch (LAMS) control or 5% or 10% butyrylated LAMS (LAMSB) for 10 days. We found that cecal but not colonic tissue weight as well as cecal and distal colonic digesta weights and fecal output were higher in LAMSB fed rats. Butyrylated LAMS lowered digesta pH throughout the large bowel. Cecal, proximal, and distal colonic butyrate pools and portal venous butyrate concentrations were higher in rats fed LAMSB. Electrically stimulated and receptor-dependent carbachol and prostaglandin E(2)-induced isotonic contractions were lower in isolated intact sections of proximal colon (P < .05) but not the terminal ileum after 10% LAMSB ingestion. These results demonstrated that elevation of butyrate levels in the large bowel of the rat correlated with reduction of contractile activity of the colonic musculature, which may assist in the reabsorption of water and minerals.


Assuntos
Butiratos/metabolismo , Colo/efeitos dos fármacos , Carboidratos da Dieta/administração & dosagem , Contração Muscular/efeitos dos fármacos , Músculo Liso/efeitos dos fármacos , Amido/farmacologia , Amilose , Animais , Ceco , Colo/metabolismo , Colo/fisiologia , Defecação/efeitos dos fármacos , Fezes , Concentração de Íons de Hidrogênio , Íleo/efeitos dos fármacos , Íleo/fisiologia , Masculino , Músculo Liso/fisiologia , Tamanho do Órgão , Veia Porta/metabolismo , Ratos , Ratos Sprague-Dawley , Amido/administração & dosagem , Amido/química , Zea mays
13.
Carcinogenesis ; 29(11): 2169-74, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18684730

RESUMO

Dietary resistant starch (RS), as a high amylose maize starch (HAMS), prevents dietary protein-induced colonocyte genetic damage in rats, possibly through the short-chain fatty acid (SCFA) butyrate produced by large bowel bacterial RS fermentation. Increasing butyrate availability may improve colonic health and dietary high amylose maize butyrylated starch (HAMSB) is an effective method of achieving this goal. In this study, rats (n = 8 per group) were fed diets containing high levels (25%) of dietary protein as casein with 10 or 20% dietary HAMSB and HAMS. Colonocyte genetic damage was measured by the comet assay and was 2-fold higher in rats fed 25% protein than those fed 15% protein (P < 0.001). Concurrent feeding of 25% protein and either HAMS or HAMSB lowered genetic damage significantly relative to a low-RS high-protein control diet. The 20% HAMSB diet was twice as effective as 20% HAMS in opposing genetic damage. Large bowel digesta butyrate was significantly increased in rats fed 20% compared with 10% HAMS and in rats fed 20% compared with 10% HAMSB. The levels were significantly higher in the HAMSB groups relative to the HAMS groups. Hepatic portal venous SCFA were higher in rats fed HAMS and highest in those fed HAMSB. Caecal digesta ammonia was increased by HAMSB and correlated negatively with digesta pH. Ammonia is cytotoxic and lower digesta pH could lower its absorption, possibly contributing to lower genetic damage. Delivery of butyrate to the large bowel by HAMSB could reduce colorectal cancer risk by preventing diet-induced colonocyte genetic damage.


Assuntos
Butiratos/química , Colo/ultraestrutura , Dano ao DNA , DNA/efeitos dos fármacos , Proteínas Alimentares/efeitos adversos , Amido/farmacologia , Animais , Peso Corporal , Ensaio Cometa , Masculino , Tamanho do Órgão , Ratos , Ratos Sprague-Dawley , Amido/administração & dosagem , Amido/química
14.
Carcinogenesis ; 29(11): 2190-4, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18701436

RESUMO

Colorectal cancer (CRC) is a major cause of death worldwide. Studies suggest that dietary fibre offers protection perhaps by increasing colonic fermentative production of butyrate. This study examined the importance of butyrate by investigating the effects of resistant starch (RS) and butyrylated-RS on azoxymethane (AOM)-induced CRC in rats. Four groups (n = 30 per group) of Sprague-Dawley rats were fed AIN-93G-based diets containing a standard low-RS maize starch (LAMS), LAMS + 3% tributyrin (LAMST), 10% high-amylose maize starch (HAMS) and 10% butyrylated HAMS (HAMSB) for 4 weeks. Rats were injected once weekly for 2 weeks with 15 mg/kg AOM, maintained on diets for 25 weeks and then killed. Butyrate concentrations in large bowel digesta were higher in rats fed HAMSB than other groups (P < 0.001); levels were similar in HAMS, LAMS and LAMST groups. The proportion of rats developing tumours were lower in HAMS and HAMSB than LAMS (P < 0.05), and the number of tumours per rat were lower in HAMSB than LAMS (P < 0.05). Caecal digesta butyrate pools and concentrations were negatively correlated with tumour size (P < 0.05). Hepatic portal plasma butyrate concentrations were higher (P < 0.001) in the HAMSB compared with other groups and negatively correlated with tumour number per rat (P < 0.009) and total tumour size for each rat (P = 0.05). HAMSB results in higher luminal butyrate than RS alone or tributyrin. This is associated with reduced tumour incidence, number and size in this rat model of CRC supporting the important protective role of butyrate. Interventional strategies designed to maximize luminal butyrate may be of protective benefit in humans.


Assuntos
Amilose/análise , Anticarcinógenos/farmacologia , Azoximetano/toxicidade , Butiratos/química , Carcinógenos/toxicidade , Neoplasias Intestinais/prevenção & controle , Amido/farmacologia , Zea mays , Animais , Anticarcinógenos/administração & dosagem , Anticarcinógenos/química , Neoplasias Intestinais/induzido quimicamente , Masculino , Ratos , Ratos Sprague-Dawley , Amido/administração & dosagem , Amido/química
15.
J Nutr ; 137(10): 2264-9, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17885009

RESUMO

Colorectal cancer (CRC) is the 3rd leading cause of cancer death in the United States and the 2nd leading cause of cancer death in Australia. Environmental factors play important roles in the multiple-stage process of CRC and nutritional intervention has been identified as playing a major role in its prevention. The aim of this study was to review systematically the scientific evidence from all studies conducted over the last decade that examined effects of garlic on CRC. Levels of evidence were ranked from level I to level V according to study designs and the quality of each study was assessed against a set of quality criteria based on those used by the National Health and Medical Research Council in Australia. One randomized controlled trial (RCT, level II) reported a statistically significant 29% reduction in both size and number of colon adenomas in CRC patients taking aged garlic extract. Five of 8 case control/cohort studies (level III) suggested a protective effect of high intake of raw/cooked garlic and 2 of 8 of these studies suggested a protective effect for distal colon. A published meta-analysis (level III) of 7 of these studies confirmed this inverse association, with a 30% reduction in relative risk. Eleven animal studies (level V) demonstrated a significant anticarcinogenic effect of garlic and/or its active constituents. On balance, there is consistent scientific evidence derived from RCT of animal studies reporting protective effects of garlic on CRC despite great heterogeneity of measures of intakes among human epidemiological studies.


Assuntos
Neoplasias Colorretais/prevenção & controle , Alho , Alho/química , Humanos , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Fatores de Risco
16.
Med J Aust ; 185(S4): S1-S24, 2006 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-17022438

RESUMO

UNLABELLED: Herbs and spices have a traditional history of use, with strong roles in cultural heritage, and in the appreciation of food and its links to health. Demonstrating the benefits of foods by scientific means remains a challenge, particularly when compared with standards applied for assessing pharmaceutical agents. Pharmaceuticals are small-molecular-weight compounds consumed in a purified and concentrated form. Food is eaten in combinations, in relatively large, unmeasured quantities under highly socialised conditions. The real challenge lies not in proving whether foods, such as herbs and spices, have health benefits, but in defining what these benefits are and developing the methods to expose them by scientific means. CULTURAL ASPECTS: The place of herbs and spices in the diet needs to be considered in reviewing health benefits. This includes definitions of the food category and the way in which benefits might be viewed, and therefore researched. Research may focus on identifying bioactive substances in herbs and spices, or on their properties as a whole food, and/or be set in the context of a dietary cuisine. THE ROLE OF HERBS AND SPICES IN HEALTH: The antioxidant properties of herbs and spices are of particular interest in view of the impact of oxidative modification of low-density lipoprotein cholesterol in the development of atherosclerosis. There is level III-3 evidence (National Health and Medical Research Council [NHMRC] levels of evidence) that consuming a half to one clove of garlic (or equivalent) daily may have a cholesterol-lowering effect of up to 9%. There is level III-1 evidence that 7.2 g of aged garlic extract has been associated with anticlotting (in-vivo studies), as well as modest reductions in blood pressure (an approximate 5.5% decrease in systolic blood pressure). A range of bioactive compounds in herbs and spices have been studied for anticarcinogenic properties in animals, but the challenge lies in integrating this knowledge to ascertain whether any effects can be observed in humans, and within defined cuisines. Research on the effects of herbs and spices on mental health should distinguish between cognitive decline associated with ageing and the acute effects of psychological and cognitive function. There is level I and II evidence for the effect of some herbal supplements on psychological and cognitive function. There is very limited scientific evidence for the effects of herbs and spices on type 2 diabetes mellitus, with the best evidence being available for the effect of ginseng on glycaemia, albeit based on four studies. More research is required, particularly examining the effects of chronic consumption patterns. With increasing interest in alternatives to non-steroidal anti-inflammatory agents in the management of chronic inflammation, research is emerging on the use of food extracts. There is level II evidence for the use of ginger in ameliorating arthritic knee pain; however, the improvement is modest and the efficacy of ginger treatment is ranked below that of ibuprofen. More definitive research is required. PUBLIC HEALTH AND DIETARY IMPLICATIONS: Recommendations for intakes of food in the Australian guide to healthy eating do not yet include suggested intakes of herbs and spices. Future consideration should be given to including more explicit recommendations about their place in a healthy diet. In addition to delivering antioxidant and other properties, herbs and spices can be used in recipes to partially or wholly replace less desirable ingredients such as salt, sugar and added saturated fat in, for example, marinades and dressings, stir-fry dishes, casseroles, soups, curries and Mediterranean-style cooking. Vegetable dishes and vegetarian options may be more appetising when prepared with herbs and spices. FUTURE DIRECTIONS: As several metabolic diseases and age-related degenerative disorders are closely associated with oxidative processes in the body, the use of herbs and spices as a source of antioxidants to combat oxidation warrants further attention. Immediate studies should focus on validating the antioxidant capacity of herbs and spices after harvest, as well as testing their effects on markers of oxidation. This will work in parallel with clinical trials that are aiming to establish antioxidants as mediators of disease prevention. From a dietary perspective, the functionality of herbs and spices will be exposed through consideration of their properties as foods. As with most foods, the real benefits of including them in the diet are likely to emerge with a better understanding of the attributes of health that are best supported by food, and in methodological developments addressing the evidence base for their effects. These developments are well underway through evidence-based frameworks for substantiating health claims related to foods. At present, recommendations are warranted to support the consumption of foods rich in bioactive components, such as herbs and spices. With time, we can expect to see a greater body of scientific evidence supporting the benefits of herbs and spices in the overall maintenance of health and protection from disease.


Assuntos
Antioxidantes/uso terapêutico , Fenômenos Fisiológicos da Nutrição/fisiologia , Plantas Medicinais , Saúde Pública , Especiarias , Antioxidantes/administração & dosagem , Antioxidantes/história , Doenças Cardiovasculares/prevenção & controle , Transtornos Cognitivos/prevenção & controle , Diabetes Mellitus Tipo 2/prevenção & controle , Medicina Baseada em Evidências , Alimentos , Tecnologia de Alimentos , Alimentos Orgânicos , História do Século XIX , História Antiga , História Medieval , Humanos , Inflamação/prevenção & controle , Neoplasias/prevenção & controle , Oxirredução , Plantas Medicinais/química , Especiarias/análise , Especiarias/história
17.
J Am Geriatr Soc ; 50(7): 1272-7, 2002 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-12133024

RESUMO

OBJECTIVES: Older people are at risk of undernutrition because of a number of physiological conditions and lifestyle factors. The purpose of this study was to explore the predictive relationship of corrected arm muscle area (CAMA) with 8-year mortality in a representative sample of older Australians. DESIGN: Prospective cohort study: The Australian Longitudinal Study of Ageing. SETTING: Community. PARTICIPANTS: One thousand three hundred ninety-six participants aged 70 and older. MEASUREMENTS: Trained observers measured baseline weight, height, mid upper arm circumference, and triceps skinfold thickness using standard techniques. Body mass index (BMI) and CAMA were calculated. Baseline BMI and CAMA measurements were categorized according to cutoff values proposed by Garrow et al. and Friedman et al., respectively. Subsequent analyses were undertaken using Cox proportional hazards regression. RESULTS: After adjustment for potential confounders (baseline age, gender, marital status, smoking, self-rated health, ability to conduct activities of daily living, comorbidity, cognition performance, and presence of depression), those older Australians with a low CAMA (

Assuntos
Antropometria/métodos , Braço/anatomia & histologia , Mortalidade/tendências , Músculo Esquelético/anatomia & histologia , Idoso , Austrália/epidemiologia , Índice de Massa Corporal , Feminino , Humanos , Masculino , Avaliação Nutricional , Estado Nutricional , Valor Preditivo dos Testes , Modelos de Riscos Proporcionais , Estudos Prospectivos , Fatores de Risco
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