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1.
Crit Rev Food Sci Nutr ; 62(21): 5824-5885, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-33775173

RESUMO

Soybeans are a rich source of isoflavones, which are classified as phytoestrogens. Despite numerous proposed benefits, isoflavones are often classified as endocrine disruptors, based primarily on animal studies. However, there are ample human data regarding the health effects of isoflavones. We conducted a technical review, systematically searching Medline, EMBASE, and the Cochrane Library (from inception through January 2021). We included clinical studies, observational studies, and systematic reviews and meta-analyses (SRMA) that examined the relationship between soy and/or isoflavone intake and endocrine-related endpoints. 417 reports (229 observational studies, 157 clinical studies and 32 SRMAs) met our eligibility criteria. The available evidence indicates that isoflavone intake does not adversely affect thyroid function. Adverse effects are also not seen on breast or endometrial tissue or estrogen levels in women, or testosterone or estrogen levels, or sperm or semen parameters in men. Although menstrual cycle length may be slightly increased, ovulation is not prevented. Limited insight could be gained about possible impacts of in utero isoflavone exposure, but the existing data are reassuring. Adverse effects of isoflavone intake were not identified in children, but limited research has been conducted. After extensive review, the evidence does not support classifying isoflavones as endocrine disruptors.


Assuntos
Disruptores Endócrinos , Isoflavonas , Estudos Clínicos como Assunto , Estrogênios , Feminino , Humanos , Isoflavonas/efeitos adversos , Isoflavonas/farmacologia , Masculino , Estudos Observacionais como Assunto , Glycine max
2.
J Anat ; 239(3): 545-556, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34032275

RESUMO

High-resolution, noninvasive and nondestructive imaging of the subepithelial structures of the larynx would enhance microanatomic tissue assessment and clinical decision making; similarly, in situ molecular profiling of laryngeal tissue would enhance biomarker discovery and pathology readout. Towards these goals, we assessed the capabilities of high-resolution magnetic resonance imaging (MRI) and matrix-assisted laser desorption/ionisation-mass spectrometry (MALDI-MS) imaging of rarely reported paediatric and adult cadaveric larynges that contained pathologies. The donors were a 13-month-old male, a 10-year-old female with an infraglottic mucus retention cyst and a 74-year-old female with advanced polypoid degeneration and a mucus retention cyst. MR and molecular imaging data were corroborated using whole-organ histology. Our MR protocols imaged the larynges at 45-117 µm2 in-plane resolution and capably resolved microanatomic structures that have not been previously reported radiographically-such as the vocal fold superficial lamina propria, vocal ligament and macula flavae; age-related tissue features-such as intramuscular fat deposition and cartilage ossification; and the lesions. Diffusion tensor imaging characterised differences in water diffusivity, primary tissue fibre orientation, and fractional anisotropy between the intrinsic laryngeal muscles, mucosae and lesions. MALDI-MS imaging revealed peptide signatures and putative protein assignments for the polypoid degeneration lesion and the N-glycan constituents of one mucus retention cyst. These imaging approaches have immediate application in experimental research and, with ongoing technology development, potential for future clinical application.


Assuntos
Músculos Laríngeos/diagnóstico por imagem , Laringe/diagnóstico por imagem , Idoso , Criança , Imagem de Tensor de Difusão , Feminino , Humanos , Lactente , Imageamento por Ressonância Magnética , Masculino , Espectrometria de Massas
3.
Eur J Nutr ; 60(8): 4635-4643, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34170392

RESUMO

PURPOSE: Resistant dextrin (RD) supplementation has been shown to alter satiety, glycaemia, and body weight, in overweight Chinese men; however, there are limited data on its effects in other demographic groups. Here, we investigated the effects of RD on satiety in healthy adults living in the United Kingdom. METHODS: 20 normal weight and 16 overweight adults completed this randomised controlled cross-over study. Either RD (14 g/day NUTRIOSE® FB06) or maltodextrin control was consumed in mid-morning and mid-afternoon preload beverages over a 28-day treatment period with crossover after a 28-day washout. During 10-h study visits (on days 1, 14, and 28 of each treatment period), satietogenic, glycaemic and anorectic hormonal responses to provided meals were assessed. RESULTS: Chronic supplementation with RD was associated with higher fasted satiety scores at day 14 (P = 0.006) and day 28 (P = 0.040), compared to control. RD also increased satiety after the mid-morning intervention drink, but it was associated with a reduction in post-meal satiety following both the lunch and evening meals (P < 0.01). The glycaemic response to the mid-morning intervention drink (0-30 min) was attenuated following RD supplementation (P < 0.01). Whilst not a primary endpoint we also observed lower systolic blood pressure at day 14 (P = 0.035) and 28 (P = 0.030), compared to day 1, following RD supplementation in the normal weight group. Energy intake and anthropometrics were unaffected. CONCLUSIONS: RD supplementation modified satiety and glycaemic responses in this cohort, further studies are required to determine longer-term effects on body weight control and metabolic markers. CLINICALTRIALS. GOV REGISTRATION: NCT02041975 (22/01/2014).


Assuntos
Dextrinas , Resposta de Saciedade , Adulto , Glicemia , Estudos Cross-Over , Suplementos Nutricionais , Ingestão de Energia , Humanos , Masculino , Saciação
4.
Eur J Nutr ; 60(3): 1263-1276, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-32651764

RESUMO

PURPOSE: Studies on broccoli (Brassica oleracea var. italica) indicate beneficial effects against a range of chronic diseases, commonly attributed to their bioactive phytochemicals. Sulforaphane, the bioactive form of glucoraphanin, is formed by the action of the indigenous enzyme myrosinase. This study explored the role that digestion and cooking practices play in bioactivity and bioavailability, especially the rarely considered dose delivered to the colon. METHODS: The antimicrobial activity of sulforaphane extracts from raw, cooked broccoli and cooked broccoli plus mustard seeds (as a source myrosinase) was assessed. The persistence of broccoli phytochemicals in the upper gastrointestinal tract was analysed in the ileal fluid of 11 ileostomates fed, in a cross-over design, broccoli soup prepared with and without mustard seeds. RESULTS: The raw broccoli had no antimicrobial activity, except against Bacillus cereus, but cooked broccoli (with and without mustard seeds) showed considerable antimicrobial activity against various tested pathogens. The recovery of sulforaphane in ileal fluids post soup consumption was < 1% but the addition of mustard seeds increased colon-available sulforaphane sixfold. However, when sulforaphane was extracted from the ileal fluid with the highest sulforaphane content and tested against Escherichia coli K12, no inhibitory effects were observed. Analysis of glucosinolates composition in ileal fluids revealed noticeable inter-individual differences, with six "responding" participants showing increases in glucosinolates after broccoli soup consumption. CONCLUSIONS: Sulforaphane-rich broccoli extracts caused potent antimicrobial effects in vitro, and the consumption of sulforaphane-enriched broccoli soup may inhibit bacterial growth in the stomach and upper small intestine, but not in the terminal ileum or the colon.


Assuntos
Anti-Infecciosos , Brassica , Culinária , Estudos Cross-Over , Glucosinolatos , Humanos , Isotiocianatos , Oximas , Extratos Vegetais/farmacologia , Sulfóxidos
5.
Nutr Res Rev ; 33(1): 145-154, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-31928558

RESUMO

A consensus workshop on low-calorie sweeteners (LCS) was held in November 2018 where seventeen experts (the panel) discussed three themes identified as key to the science and policy of LCS: (1) weight management and glucose control; (2) consumption, safety and perception; (3) nutrition policy. The aims were to identify the reliable facts on LCS, suggest research gaps and propose future actions. The panel agreed that the safety of LCS is demonstrated by a substantial body of evidence reviewed by regulatory experts and current levels of consumption, even for high users, are within agreed safety margins. However, better risk communication is needed. More emphasis is required on the role of LCS in helping individuals reduce their sugar and energy intake, which is a public health priority. Based on reviews of clinical evidence to date, the panel concluded that LCS can be beneficial for weight management when they are used to replace sugar in products consumed in the diet (without energy substitution). The available evidence suggests no grounds for concerns about adverse effects of LCS on sweet preference, appetite or glucose control; indeed, LCS may improve diabetic control and dietary compliance. Regarding effects on the human gut microbiota, data are limited and do not provide adequate evidence that LCS affect gut health at doses relevant to human use. The panel identified research priorities, including collation of the totality of evidence on LCS and body weight control, monitoring and modelling of LCS intakes, impacts on sugar reduction and diet quality and developing effective communication strategies to foster informed choice. There is also a need to reconcile policy discrepancies between organisations and reduce regulatory hurdles that impede low-energy product development and reformulation.


Assuntos
Ingestão de Energia , Edulcorantes , Apetite , Consenso , Dieta , Humanos , Edulcorantes/efeitos adversos
6.
Eur J Nutr ; 58(6): 2377-2391, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-30066177

RESUMO

PURPOSE: Watercress is a rich source of phytochemicals with anticancer potential, including phenethyl isothiocyanate (PEITC). We examined the potential for watercress extracts and PEITC to increase the DNA damage caused by ionising radiation (IR) in breast cancer cells and to be protective against radiation-induced collateral damage in healthy breast cells. The metabolic events that mediate such responses were explored using metabolic profiling. METHODS: 1H nuclear magnetic resonance spectroscopy-based metabolic profiling was coupled with DNA damage-related assays (cell cycle, Comet assay, viability assays) to profile the comparative effects of watercress and PEITC in MCF-7 breast cancer cells and MCF-10A non-tumorigenic breast cells with and without exposure to IR. RESULTS: Both the watercress extract and PEITC-modulated biosynthetic pathways of lipid and protein synthesis and resulted in changes in cellular bioenergetics. Disruptions to the redox balance occurred with both treatments in the two cell lines, characterised by shifts in the abundance of glutathione. PEITC enhanced the sensitivity of the breast cancer cells to IR increasing the effectiveness of the cancer-killing process. In contrast, watercress-protected non-tumorigenic breast cells from radiation-induced damage. These effects were driven by changes in the cellular content of the antioxidant glutathione following exposure to PEITC and other phytochemicals in watercress. CONCLUSION: These findings support the potential prophylactic impact of watercress during radiotherapy. Extracted compounds from watercress and PEITC differentially modulate cellular metabolism collectively enhancing the therapeutic outcomes of radiotherapy.


Assuntos
Anticarcinógenos/metabolismo , Anticarcinógenos/farmacologia , Isotiocianatos/metabolismo , Isotiocianatos/farmacologia , Nasturtium/metabolismo , Radiação Ionizante , Apoptose , Linhagem Celular Tumoral , Humanos , Células MCF-7 , Espectroscopia de Ressonância Magnética
7.
J Nutr ; 148(7): 1186S-1205S, 2018 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-29982648

RESUMO

Steviol glycoside sweeteners are extracted and purified from the Stevia rebaudiana Bertoni plant, a member of the Asteraceae (Compositae) family that is native to South America, where it has been used for its sweet properties for hundreds of years. With continued increasing rates of obesity, diabetes, and other related comorbidities, in conjunction with global public policies calling for reductions in sugar intake as a means to help curb these issues, low- and no-calorie sweeteners (LNCSs, also known as high-potency sweeteners) such as stevia are gaining interest among consumers and food manufacturers. This appeal is related to stevia being plant-based, zero calorie and with a sweet taste that is 50-350 times sweeter than sugar, making it an excellent choice for use in sugar- and calorie-reduced food and beverage products. Despite the fact that the safety of stevia has been affirmed by several food regulatory and safety authorities around the world, insufficient education about stevia's safety and benefits, including continuing concern with regard to the safety of LNCSs in general, deters health professionals and consumers from recommending or using stevia. Therefore, the aim of this review and the stevia symposium that preceded this review at the ASN's annual conference in 2017 was to examine, in a comprehensive manner, the state of the science for stevia, its safety and potential health benefits, and future research and application. Topics covered included metabolism, safety and acceptable intake, dietary exposure, impact on blood glucose and insulin concentrations, energy intake and weight management, blood pressure, dental caries, naturality and processing, taste and sensory properties, regulatory status, consumer insights, and market trends. Data for stevia are limited in the case of energy intake and weight management as well as for the gut microbiome; therefore, the broader literature on LNCSs was reviewed at the symposium and therefore is also included in this review.


Assuntos
Diterpenos do Tipo Caurano/farmacologia , Glucosídeos/farmacologia , Extratos Vegetais/química , Folhas de Planta/química , Stevia/química , Edulcorantes , Diterpenos do Tipo Caurano/química , Glucosídeos/química , Humanos
8.
Eur J Nutr ; 57(1): 1-24, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28393285

RESUMO

The diverse microbial community that inhabits the human gut has an extensive metabolic repertoire that is distinct from, but complements the activity of mammalian enzymes in the liver and gut mucosa and includes functions essential for host digestion. As such, the gut microbiota is a key factor in shaping the biochemical profile of the diet and, therefore, its impact on host health and disease. The important role that the gut microbiota appears to play in human metabolism and health has stimulated research into the identification of specific microorganisms involved in different processes, and the elucidation of metabolic pathways, particularly those associated with metabolism of dietary components and some host-generated substances. In the first part of the review, we discuss the main gut microorganisms, particularly bacteria, and microbial pathways associated with the metabolism of dietary carbohydrates (to short chain fatty acids and gases), proteins, plant polyphenols, bile acids, and vitamins. The second part of the review focuses on the methodologies, existing and novel, that can be employed to explore gut microbial pathways of metabolism. These include mathematical models, omics techniques, isolated microbes, and enzyme assays.


Assuntos
Bactérias/metabolismo , Alimentos , Microbioma Gastrointestinal/fisiologia , Promoção da Saúde , Bactérias/enzimologia , Ácidos e Sais Biliares/metabolismo , Dieta , Carboidratos da Dieta/metabolismo , Proteínas Alimentares/metabolismo , Ácidos Graxos/metabolismo , Humanos , Metagenômica , Modelos Teóricos , Compostos Fitoquímicos/metabolismo , Plantas Comestíveis/química , Plantas Comestíveis/metabolismo , Polifenóis/metabolismo , Proteômica , Vitaminas/biossíntese
9.
Eur J Nutr ; 57(1): 25-49, 2018 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-29086061

RESUMO

PURPOSE: There is considerable interest in the effects of the intestinal microbiota (IM) composition, its activities in relation with the metabolism of dietary substrates and the impact these effects may have in the development and prevention of certain non-communicable diseases. It is acknowledged that a complex interdependence exists between the IM and the mammalian host and that the IM possesses a far greater diversity of genes and repertoire of metabolic and enzymatic capabilities than their hosts. However, full knowledge of the metabolic activities and interactions of the IM and the functional redundancy that may exist are lacking. Thus, the current review aims to assess recent literature relating to the role played by the IM in the absorption and metabolism of key nutrients and non-nutrients. METHODS: A systematic review (PROSPERO registration: CRD42015019087) was carried out focussing on energy and the following candidate dietary substrates: protein, carbohydrate, fat, fibre, resistant starch (RS), and polyphenols to further understand the effect of the IM on the dietary substrates and the resulting by-products and host impacts. Particular attention was paid to the characterisation of the IM which are predominantly implicated in each case, changes in metabolites, and indirect markers and any potential impacts on the host. RESULTS: Studies show that the IM plays a key role in the metabolism of the substrates studied. However, with the exception of studies focusing on fibre and polyphenols, there have been relatively few recent human studies specifically evaluating microbial metabolism. In addition, comparison of the effects of the IM across studies was difficult due to lack of specific analysis/description of the bacteria involved. Considerable animal-derived data exist, but experience suggests that care must be taken when extrapolating these results to humans. Nevertheless, it appears that the IM plays a role in energy homeostasis and that protein microbial breakdown and fermentation produced ammonia, amines, phenols and branch chain fatty acids, and a greater diversity in the microbes present. Few recent studies appear to have evaluated the effect of the IM composition and metabolism per se in relation with digestible dietary carbohydrate or fat in humans. Intakes of RS and prebiotics altered levels of specific taxa that selectively metabolised specific prebiotic/carbohydrate-type substances and levels of bifidobacteria and lactobacilli were observed to increase. In controlled human studies, consistent data exist that show a correlation between the intake of fibre and an increase in bifidobacteria and short-chain fatty acids, in particular butyrate, which leads to lower intestinal pH. Dietary polyphenols rely on modification either by host digestive enzymes or those derived from the IM for absorption to occur. In the polyphenol-related studies, a large amount of inter-individual variation was observed in the microbial metabolism and absorption of certain polyphenols. CONCLUSIONS: The systematic review demonstrates that the IM plays a major role in the breakdown and transformation of the dietary substrates examined. However, recent human data are limited with the exception of data from studies examining fibres and polyphenols. Results observed in relation with dietary substrates were not always consistent or coherent across studies and methodological limitations and differences in IM analyses made comparisons difficult. Moreover, non-digestible components likely to reach the colon are often not well defined or characterised in studies making comparisons between studies difficult if not impossible. Going forward, further rigorously controlled randomised human trials with well-defined dietary substrates and utilizing omic-based technologies to characterise and measure the IM and their functional activities will advance the field. Current evidence suggests that more detailed knowledge of the metabolic activities and interactions of the IM hold considerable promise in relation with host health.


Assuntos
Bactérias/metabolismo , Alimentos , Microbioma Gastrointestinal/fisiologia , Animais , Carboidratos da Dieta/metabolismo , Gorduras na Dieta/metabolismo , Fibras na Dieta/metabolismo , Proteínas Alimentares/metabolismo , Digestão , Metabolismo Energético , Homeostase , Humanos , Isoflavonas/metabolismo , Polifenóis/metabolismo , Amido/metabolismo
10.
Eur J Nutr ; 56(4): 1421-1432, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-26951205

RESUMO

PURPOSE: Dietary polyphenols have been demonstrated to favourably modify a number of cardiovascular risk markers such as blood pressure (BP), endothelial function and plasma lipids. We conducted a randomised, double-blind, controlled, crossover trial to investigate the effects of a phenolic-rich olive leaf extract (OLE) on BP and a number of associated vascular and metabolic measures. METHODS: A total of 60 pre-hypertensive [systolic blood pressure (SBP): 121-140 mmHg; diastolic blood pressure (DBP): 81-90 mmHg] males [mean age 45 (±SD 12.7 years, BMI 26.7 (±3.21) kg/m2] consumed either OLE (136 mg oleuropein; 6 mg hydroxytyrosol) or a polyphenol-free control daily for 6 weeks before switching to the alternate arm after a 4-week washout. RESULTS: Daytime [-3.95 (±SD 11.48) mmHg, p = 0.027] and 24-h SBP [-3.33 (±SD 10.81) mmHg, p = 0.045] and daytime and 24-h DBP [-3.00 (±SD 8.54) mmHg, p = 0.025; -2.42 (±SD 7.61) mmHg, p = 0.039] were all significantly lower following OLE intake, relative to the control. Reductions in plasma total cholesterol [-0.32 (±SD 0.70) mmol/L, p = 0.002], LDL cholesterol [-0.19 (±SD 0.56) mmol/L, p = 0.017] and triglycerides [-0.18 (±SD 0.48), p = 0.008] were also induced by OLE compared to control, whilst a reduction in interleukin-8 [-0.63 (±SD 1.13) pg/ml; p = 0.026] was also detected. Other markers of inflammation, vascular function and glucose metabolism were not affected. CONCLUSION: Our data support previous research, suggesting that OLE intake engenders hypotensive and lipid-lowering effects in vivo.


Assuntos
Colesterol/sangue , Olea/química , Extratos Vegetais/farmacologia , Folhas de Planta/química , Polifenóis/farmacologia , Triglicerídeos/sangue , Adulto , Idoso , Biomarcadores/sangue , Pressão Sanguínea/efeitos dos fármacos , Índice de Massa Corporal , Proteína C-Reativa/metabolismo , Estudos Cross-Over , Citocinas/sangue , Método Duplo-Cego , Humanos , Inflamação/sangue , Glucosídeos Iridoides , Iridoides/farmacologia , Masculino , Pessoa de Meia-Idade , Fatores de Risco , Adulto Jovem
11.
Molecules ; 22(7)2017 Jun 29.
Artigo em Inglês | MEDLINE | ID: mdl-28661446

RESUMO

Here, the effects of consuming polyphenol-rich olive products, including olive leaves, their crude extract, and extra virgin olive oil, on aspects of the metabolic syndrome are reviewed. We have sought to summarize the available scientific evidence from dietary intervention trials demonstrating a role for these phytochemicals in ameliorating aberrant glucose metabolism, high blood pressure and elevated blood lipids, and we discuss the potential mechanisms underpinning these observations. Searches for relevant literature published in English were conducted via PubMed and Science Direct. Based on published dietary intervention studies, there is convincing evidence to show that olive polyphenols, independently of olive lipids, reduce risk factors for metabolic syndrome, in particular by improving blood sugar and blood pressure control, and in reducing low density lipoprotein oxidation. There is more limited evidence to suggest that the consumption of olive polyphenols or related products can reduce body weight and visceral fat or impede weight gain, and similarly there are some limited data suggesting improved lipid profiles. There is some mechanistic data to support observations made in human volunteers, but further work is needed in this area. The consumption of olive polyphenols within the context of a healthy pattern of food intake may, in part, explain the reduced risk of metabolic disease associated with adherence to the Mediterranean diet.


Assuntos
Dieta , Síndrome Metabólica/etiologia , Olea/química , Extratos Vegetais , Polifenóis , Animais , Dieta Mediterrânea , Suscetibilidade a Doenças , Dislipidemias/epidemiologia , Dislipidemias/etiologia , Dislipidemias/metabolismo , Humanos , Hipertensão/epidemiologia , Hipertensão/etiologia , Hipertensão/metabolismo , Metabolismo dos Lipídeos , Síndrome Metabólica/epidemiologia , Síndrome Metabólica/metabolismo , Obesidade Abdominal/epidemiologia , Obesidade Abdominal/etiologia , Obesidade Abdominal/metabolismo , Olea/metabolismo , Azeite de Oliva/análise , Azeite de Oliva/química , Extratos Vegetais/análise , Extratos Vegetais/química , Polifenóis/análise , Polifenóis/química , Fatores de Risco
12.
J Nutr ; 146(6): 1197-203, 2016 06.
Artigo em Inglês | MEDLINE | ID: mdl-27170728

RESUMO

BACKGROUND: Prospective cohort studies show that higher dietary fiber intake is associated with reduced cardiovascular disease risk, yet the impact on postprandial glucose and insulin responses is unclear. OBJECTIVE: This study aims to evaluate the effects of orange beverages with differing fiber concentrations on postprandial glycemic responses (secondary outcome measure) after a sequential breakfast and lunch challenge in men with increased cardiometabolic risk. METHODS: Thirty-six men (aged 30-65 y; body mass index 25-30 kg/m(2): fasting triacylglycerol or total cholesterol concentrations: 0.8-2.2 or 6.0-8.0 mmol/L, respectively) were provided with a high-fat mixed breakfast and were randomly assigned to consume 240 mL Tropicana (PepsiCo, Inc.) pure premium orange juice without pulp (OJ), OJ with 5.5 g added orange pomace fiber (OPF), juice made from lightly blended whole orange, or an isocaloric sugar-matched control (Control) on 4 occasions separated by 2 wk. A medium-fat mixed lunch was provided at 330 min. Blood samples were collected before breakfast and on 11 subsequent occasions for 420 min (3 time points postlunch) to determine postprandial glucose, insulin, lipid, and inflammatory biomarker responses. Repeated-measures ANOVA was used for data analysis. RESULTS: OPF significantly (P < 0.05) reduced the maximal change in glucose concentrations (1.9 ± 0.21 mmol/L) reached after breakfast compared with other treatments (2.3-2.4 mmol/L) and after lunch (3.0 ± 0.05 mmol/L) compared with OJ (3.6 ± 0.05 mmol/L). The maximal change in insulin concentration (313 ± 25 pmol/L) was also lower compared with Control (387 ± 30 pmol/L) and OJ (418 ± 39 pmol/L) after breakfast. OPF significantly delayed the time to reach the peak glucose concentration compared with Control and OJ, and of insulin compared with Control after breakfast. CONCLUSION: OPF consumed with breakfast may lower postprandial glycemic and insulinemic responses to typical meal ingestion in men with increased cardiometabolic risk. This trial is registered at clinicaltrials.gov as NCT01963416.


Assuntos
Glicemia/metabolismo , Citrus sinensis , Sucos de Frutas e Vegetais , Insulina/sangue , Adulto , Idoso , Biomarcadores/sangue , Índice de Massa Corporal , Doenças Cardiovasculares/epidemiologia , Colesterol/sangue , Estudos Cross-Over , Fibras na Dieta/administração & dosagem , Método Duplo-Cego , Ácidos Graxos não Esterificados/sangue , Índice Glicêmico , Humanos , Masculino , Refeições , Síndrome Metabólica/epidemiologia , Pessoa de Meia-Idade , Período Pós-Prandial , Fatores de Risco , Triglicerídeos/sangue
13.
Br J Nutr ; 115(7): 1240-53, 2016 Apr 14.
Artigo em Inglês | MEDLINE | ID: mdl-26879487

RESUMO

Brown seaweeds such as Ascophyllum nodosum are a rich source of phlorotannins (oligomers and polymers of phloroglucinol units), a class of polyphenols that are unique to Phaeophyceae. At present, there is no information on the bioavailability of seaweed polyphenols and limited evidence on their bioactivity in vivo. Consequently, we investigated the gastrointestinal modifications in vitro of seaweed phlorotannins from A. nodosum and their bioavailability and effect on inflammatory markers in healthy participants. In vitro, some phlorotannin oligomers were identified after digestion and colonic fermentation. In addition, seven metabolites corresponding to in vitro-absorbed metabolites were identified. Urine and plasma samples contained a variety of metabolites attributed to both unconjugated and conjugated metabolites (glucuronides and/or sulphates). In both urine and plasma, the majority of the metabolites were found in samples collected at late time points (6-24 h), suggesting colonic metabolism of high-molecular-weight phlorotannins, with three phlorotannin oligomers (hydroxytrifuhalol A, 7-hydroxyeckol, C-O-C dimer of phloroglucinol) identified in urine samples. A significant increase of the cytokine IL-8 was also observed. Our study shows for the first time that seaweed phlorotannins are metabolised and absorbed, predominantly in the large intestine, and there is a large inter-individual variation in their metabolic profile. Three phlorotannin oligomers present in the capsule are excreted in urine. Our study is the first investigation of the metabolism and bioavailability of seaweed phlorotannins and the role of colonic biotransformation. In addition, IL-8 is a possible target for phlorotannin bioactivity.


Assuntos
Trato Gastrointestinal/metabolismo , Inflamação , Phaeophyceae/química , Floroglucinol/metabolismo , Floroglucinol/farmacocinética , Adolescente , Adulto , Idoso , Disponibilidade Biológica , Biomarcadores/sangue , Biomarcadores/urina , Cromatografia Líquida de Alta Pressão , Citocinas/sangue , Digestão , Feminino , Humanos , Interleucina-8/sangue , Masculino , Pessoa de Meia-Idade , Fenóis/sangue , Fenóis/urina , Floroglucinol/farmacologia , Polímeros/metabolismo , Polímeros/farmacocinética
15.
J Nat Prod ; 79(10): 2606-2615, 2016 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-27643821

RESUMO

Ileostomy studies provide a unique insight into the digestion of foods, allowing identification of physiologically relevant dietary phytochemicals and their metabolites that are important to gut health. We previously reported an increase of components, including novel triterpenoids, in ileal fluids of 11 ileostomates following consumption of raspberries using nontargeted LC-MSn techniques in combination with data deconvolution software. The current study focused on components that consistently decreased postsupplementation. After data deconvolution, 32 components were identified that met exclusion parameters of m/z signals and which decreased significantly in ileal fluids from eight of 11 participants post-raspberry supplementation. Two-thirds of these components were identified putatively from their MS properties. Consistent decreases were observed in components that possibly reflected "washing out" of presupplementation intake of common foods/drinks including (poly)phenol metabolites. Metabolites associated with fat metabolism such as hydroxylated fatty acids and cholate-type bile acids were specifically reduced. However, more directed re-examination of the data revealed that although some cholates were consistently reduced, the more polar glyco- and tauro-linked bile acid derivatives increased consistently, by as much as 100-fold over presupplementation levels. The possible reasons for these substantial alterations in bile acid composition in ileal fluids in response to raspberry intake are discussed.


Assuntos
Ácidos e Sais Biliares/metabolismo , Suplementos Nutricionais , Íleo/metabolismo , Rubus/química , Ácidos e Sais Biliares/química , Cromatografia Líquida , Humanos , Masculino , Estrutura Molecular
16.
Appetite ; 107: 478-485, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27578252

RESUMO

Dietary fibre has been shown to increase subjective satiating ratings. However data from human trials has produced mixed results, possibly due to different types of fibre which have diverse physicochemical properties and gastrointestinal transit behaviour. The aim of study 1 was to investigate whether orange juice (OJ) with 5.5 g of added orange pomace fibre (OPF) was as satiating as whole orange (WO, chopped and blended to a puree/liquid) compared with OJ. Study 2 was to evaluate the dose-dependent satiating effect of OPF delivered in an orange-flavoured beverage. Both studies were randomized, controlled, double blind, cross over in design with 4 intervention arms in study 1 including OJ, OPF, WO, and water, and 3 arms in study 2: orange-flavoured beverage with low (2.5 g) and high (5.5 g) dose of OPF (LD-OPF and HD-OPF), and orange-flavoured beverage without fibre (Control). Volunteers were asked to response to 8 questions relating to hunger, fullness, desire to eat, thirst and discomfort by visual analogue scale (VAS) for each question. Differences were detected in least squares mean estimates of composite satiety scores and each individual question with statistical modelling to adjust for differences in baseline scores. Addition of 5.5 g OPF either to OJ or to orange-flavoured beverage significantly increased the composite satiety scores compared with OJ (P < 0.0001) or Control (P < 0.0001), and the effect was comparative to WO. LD-OPF showed some satiating effect (less desire to eat) compared with Control (P = 0.038), though less effective than HD-OPF (P = 0.043). In conclusion, the addition of OPF to OJ was as effective at increasing satiety as WO consumption compared with OJ; and there was a trend of dose-dependent effect of OPF on satiety compared with the control.


Assuntos
Bebidas , Citrus sinensis , Fibras na Dieta/administração & dosagem , Fome/efeitos dos fármacos , Saciação/efeitos dos fármacos , Adulto , Estudos Cross-Over , Método Duplo-Cego , Feminino , Sucos de Frutas e Vegetais/análise , Voluntários Saudáveis , Humanos , Masculino , Sede/efeitos dos fármacos
17.
Br J Nutr ; 114(1): 75-83, 2015 Jul 14.
Artigo em Inglês | MEDLINE | ID: mdl-26051429

RESUMO

The leaves of the olive plant (Olea europaea) are rich in polyphenols, of which oleuropein and hydroxytyrosol (HT) are most characteristic. Such polyphenols have been demonstrated to favourably modify a variety of cardiovascular risk factors. The aim of the present intervention was to investigate the influence of olive leaf extract (OLE) on vascular function and inflammation in a postprandial setting and to link physiological outcomes with absorbed phenolics. A randomised, double-blind, placebo-controlled, cross-over, acute intervention trial was conducted with eighteen healthy volunteers (nine male, nine female), who consumed either OLE (51 mg oleuropein; 10 mg HT), or a matched control (separated by a 4-week wash out) on a single occasion. Vascular function was measured by digital volume pulse (DVP), while blood collected at baseline, 1, 3 and 6 h was cultured for 24 h in the presence of lipopolysaccharide in order to investigate effects on cytokine production. Urine was analysed for phenolic metabolites by HPLC. DVP-stiffness index and ex vivo IL-8 production were significantly reduced (P< 0.05) after consumption of OLE compared to the control. These effects were accompanied by the excretion of several phenolic metabolites, namely HT and oleuropein derivatives, which peaked in urine after 8-24 h. The present study provides the first evidence that OLE positively modulates vascular function and IL-8 production in vivo, adding to growing evidence that olive phenolics could be beneficial for health.


Assuntos
Vasos Sanguíneos/fisiologia , Citocinas/sangue , Inflamação/prevenção & controle , Iridoides/administração & dosagem , Olea , Folhas de Planta/química , Disponibilidade Biológica , Vasos Sanguíneos/efeitos dos fármacos , Estudos Cross-Over , Método Duplo-Cego , Feminino , Humanos , Inflamação/sangue , Glucosídeos Iridoides , Iridoides/farmacocinética , Masculino , Fenóis/farmacocinética , Fenóis/urina , Placebos , Extratos Vegetais/administração & dosagem , Extratos Vegetais/química , Pulso Arterial , Rigidez Vascular
18.
Br J Nutr ; 114(8): 1226-36, 2015 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-26428278

RESUMO

The reported inverse association between the intake of plant-based foods and a reduction in the prevalence of colorectal cancer may be partly mediated by interactions between insoluble fibre and (poly)phenols and the intestinal microbiota. In the present study, we assessed the impact of palm date consumption, rich in both polyphenols and fibre, on the growth of colonic microbiota and markers of colon cancer risk in a randomised, controlled, cross-over human intervention study. A total of twenty-two healthy human volunteers were randomly assigned to either a control group (maltodextrin-dextrose, 37·1 g) or an intervention group (seven dates, approximately 50 g). Each arm was of 21 d duration and was separated by a 14-d washout period in a cross-over manner. Changes in the growth of microbiota were assessed by fluorescence in situ hybridisation analysis, whereas SCFA levels were assessed using HPLC. Further, ammonia concentrations, faecal water genotoxicity and anti-proliferation ability were also assessed using different assays, which included cell work and the Comet assay. Accordingly, dietary intakes, anthropometric measurements and bowel movement assessment were also carried out. Although the consumption of dates did not induce significant changes in the growth of select bacterial groups or SCFA, there were significant increases in bowel movements and stool frequency (P<0·01; n 21) and significant reductions in stool ammonia concentration (P<0·05; n 21) after consumption of dates, relative to baseline. Furthermore, date fruit intake significantly reduced genotoxicity in human faecal water relative to control (P<0·01; n 21). Our data indicate that consumption of date fruit may reduce colon cancer risk without inducing changes in the microbiota.


Assuntos
Dieta , Frutas , Intestino Grosso/microbiologia , Microbiota , Phoeniceae , Adolescente , Adulto , Amônia/análise , Bacteroides/isolamento & purificação , Bifidobacterium/isolamento & purificação , Índice de Massa Corporal , Proliferação de Células , Colesterol/sangue , Clostridium/isolamento & purificação , Colo/microbiologia , Neoplasias do Colo/prevenção & controle , Contagem de Colônia Microbiana , Estudos Cross-Over , Dano ao DNA , Gorduras na Dieta/administração & dosagem , Fibras na Dieta/administração & dosagem , Proteínas Alimentares/administração & dosagem , Ingestão de Energia , Enterococcus/isolamento & purificação , Eubacterium/isolamento & purificação , Fezes/química , Fezes/microbiologia , Feminino , Células HT29 , Humanos , Hibridização in Situ Fluorescente , Lactobacillus/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Ruminococcus/isolamento & purificação , Triglicerídeos/sangue , Adulto Jovem
19.
BMC Infect Dis ; 14: 240, 2014 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-24886045

RESUMO

BACKGROUND: The hippocampus undergoes apoptosis in experimental pneumococcal meningitis leading to neurofunctional deficits in learning and memory function. The aim of the present study was 1) to investigate hippocampal apparent diffusion coefficient (ADC) and volume with MRI during the course of experimental pneumococcal meningitis, 2) to explore the influence of accompanying bacteremia on hippocampal water distribution and volume, 3) and to correlate these findings to the extent of apoptosis in the hippocampus. METHODS: Experimental meningitis in rats was induced by intracisternal injection of live pneumococci. The study comprised of four experimental groups. I. Uninfected controls (n = 8); II. Meningitis (n = 11); III. Meningitis with early onset bacteremia by additional i.v. injection of live pneumococci (n = 10); IV. Meningitis with attenuated bacteremia by treatment with serotype-specific anti-pneumococcal antibodies (n = 14). T2 and diffusion weighted MR images were used to analyze changes in hippocampus volume and water diffusion (ADC). The results were correlated to ADC of the cortex, to ventricular volume, and to the extent of hippocampal apoptosis. RESULTS: Both ADC and the volume of hippocampus were significantly increased in meningitis rats compared to uninfected controls (Kruskal-Wallis test, p = 0.0001, Dunns Post Test, p < 0.05), and were significantly increased in meningitis rats with an early onset bacteremia as compared to meningitis rats with attenuated bacteremia (p < 0.05). Hippocampal ADC and the volume and size of brain ventricles were positively correlated (Spearman Rank, p < 0.05), whereas no association was found between ADC or volume and the extent of apoptosis (p > 0.05). CONCLUSIONS: In experimental meningitis increase in volume and water diffusion of the hippocampus are significantly associated with accompanying bacteremia.


Assuntos
Bacteriemia/metabolismo , Hipocampo/metabolismo , Meningite Pneumocócica/metabolismo , Água/metabolismo , Animais , Apoptose , Bacteriemia/microbiologia , Bacteriemia/patologia , Córtex Cerebral/metabolismo , Ventrículos Cerebrais/patologia , Difusão , Modelos Animais de Doenças , Hipocampo/patologia , Imageamento por Ressonância Magnética , Masculino , Meningite Pneumocócica/patologia , Ratos , Ratos Wistar , Streptococcus pneumoniae
20.
Eur J Nutr ; 53(1): 345-50, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23568763

RESUMO

PURPOSE: Soy isoflavones may inhibit tumor cell invasion and metastasis via their effects on matrix metalloproteinases (MMPs) and their tissue inhibitors (TIMPs). The current study investigates the effects of daidzein, R- and S-equol on the invasion of MDA-MB-231 human breast cancer cells and the effects of these compounds on MMP/TIMP expression at the mRNA level. METHODS: The anti-invasive effects of daidzein, R- and S-equol (0, 2.5, 10, 50 µM) on MDA-MB-231 cells were determined using the Matrigel invasion assay following 48-h exposure. Effects on MMP-2, MMP-9, TIMP-1 and TIMP-2 expression were assessed using real-time PCR. Chiral HPLC analysis was used to determine intracellular concentrations of R- and S-equol. RESULTS: The invasive capacity of MDA-MB-231 cells was significantly reduced (by approximately 50-60 %) following treatment with 50 µM daidzein, R- or S-equol. Anti-invasive effects were also observed with R-equol at 2.5 and 10 µM though overall equipotent effects were induced by all compounds. Inhibition of invasion induced by all three compounds at 50 µM was associated with the down-regulation of MMP-2, while none of the compounds tested significantly affected the expression levels of MMP-9, TIMP-1 or TIMP-2 at this concentration. Following exposure to media containing 50 µM R- or S-equol for 48-h intracellular concentrations of R- and S-equol were 4.38 ± 1.17 and 3.22 ± 0.47 nM, respectively. CONCLUSION: Daidzein, R- and S-equol inhibit the invasion of MDA-MB-231 human breast cancer cells in part via the down-regulation of MMP-2 expression, with equipotent effects observed for the parent isoflavone daidzein and the equol enantiomers.


Assuntos
Regulação para Baixo , Equol/farmacologia , Glycine max/química , Isoflavonas/farmacologia , Metaloproteinase 2 da Matriz/metabolismo , Neoplasias da Mama/metabolismo , Linhagem Celular Tumoral , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Inibidor Tecidual de Metaloproteinase-1/genética , Inibidor Tecidual de Metaloproteinase-1/metabolismo , Inibidor Tecidual de Metaloproteinase-2/genética , Inibidor Tecidual de Metaloproteinase-2/metabolismo
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