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1.
Int J Mol Sci ; 24(4)2023 Feb 11.
Artigo em Inglês | MEDLINE | ID: mdl-36835055

RESUMO

Probiotic bacteria have many protective effects against inflammatory disorders, though the mechanisms underlying their actions are poorly understood. The Lab4b consortium of probiotics contains four strains of lactic acid bacteria and bifidobacteria that are reflective of the gut of newborn babies and infants. The effect of Lab4b on atherosclerosis, an inflammatory disorder of the vasculature, has not yet been determined and was investigated on key processes associated with this disease in human monocytes/macrophages and vascular smooth muscle cells in vitro. The Lab4b conditioned medium (CM) attenuated chemokine-driven monocytic migration, monocyte/macrophage proliferation, uptake of modified LDL and macropinocytosis in macrophages together with the proliferation and platelet-derived growth factor-induced migration of vascular smooth muscle cells. The Lab4b CM also induced phagocytosis in macrophages and cholesterol efflux from macrophage-derived foam cells. The effect of Lab4b CM on macrophage foam cell formation was associated with a decrease in the expression of several key genes implicated in the uptake of modified LDL and induced expression of those involved in cholesterol efflux. These studies reveal, for the first time, several anti-atherogenic actions of Lab4b and strongly implicate further studies in mouse models of the disease in vivo and in clinical trials.


Assuntos
Aterosclerose , Probióticos , Animais , Camundongos , Recém-Nascido , Humanos , Macrófagos/metabolismo , Células Espumosas/metabolismo , Aterosclerose/metabolismo , Colesterol/metabolismo , Lipoproteínas LDL/metabolismo
2.
Int J Mol Sci ; 24(5)2023 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-36902113

RESUMO

Aging and metabolic syndrome are associated with neurodegenerative pathologies including Alzheimer's disease (AD) and there is growing interest in the prophylactic potential of probiotic bacteria in this area. In this study, we assessed the neuroprotective potential of the Lab4P probiotic consortium in both age and metabolically challenged 3xTg-AD mice and in human SH-SY5Y cell culture models of neurodegeneration. In mice, supplementation prevented disease-associated deteriorations in novel object recognition, hippocampal neurone spine density (particularly thin spines) and mRNA expression in hippocampal tissue implying an anti-inflammatory impact of the probiotic, more notably in the metabolically challenged setting. In differentiated human SH-SY5Y neurones challenged with ß-Amyloid, probiotic metabolites elicited a neuroprotective capability. Taken together, the results highlight Lab4P as a potential neuroprotective agent and provide compelling support for additional studies in animal models of other neurodegenerative conditions and human studies.


Assuntos
Doença de Alzheimer , Neuroblastoma , Camundongos , Humanos , Animais , Doença de Alzheimer/metabolismo , Proteínas tau/metabolismo , Camundongos Transgênicos , Neuroblastoma/patologia , Peptídeos beta-Amiloides/metabolismo , Linhagem Celular , Cognição , Modelos Animais de Doenças
3.
Clin Immunol ; 183: 63-74, 2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28689782

RESUMO

Since the 1970s, the role of infectious diseases in the pathogenesis of Graves' disease (GD) has been an object of intensive research. The last decade has witnessed many studies on Yersinia enterocolitica, Helicobacter pylori and other bacterial organisms and their potential impact on GD. Retrospective, prospective and molecular binding studies have been performed with contrary outcomes. Until now it is not clear whether bacterial infections can trigger autoimmune thyroid disease. Common risk factors for GD (gender, smoking, stress, and pregnancy) reveal profound changes in the bacterial communities of the gut compared to that of healthy controls but a pathogenetic link between GD and dysbiosis has not yet been fully elucidated. Conventional bacterial culture, in vitro models, next generation and high-throughput DNA sequencing are applicable methods to assess the impact of bacteria in disease onset and development. Further studies on the involvement of bacteria in GD are needed and may contribute to the understanding of pathogenetic processes. This review will examine available evidence on the subject.


Assuntos
Doenças Autoimunes/imunologia , Microbioma Gastrointestinal/imunologia , Doenças da Glândula Tireoide/imunologia , Doenças Autoimunes/microbiologia , Autoimunidade/imunologia , Microbioma Gastrointestinal/genética , Doença de Graves/imunologia , Doença de Graves/microbiologia , Doença de Hashimoto/imunologia , Doença de Hashimoto/microbiologia , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Tolerância Imunológica/imunologia , Microbiota/genética , Microbiota/imunologia , Linfócitos T/imunologia , Doenças da Glândula Tireoide/microbiologia , Tireoidite Autoimune/imunologia , Tireoidite Autoimune/microbiologia
5.
Nutr J ; 12: 7, 2013 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-23297818

RESUMO

BACKGROUND: Assessment of cardiovascular disease (CVD) risk factors can predict clinical manifestations of atherosclerosis in adulthood. In this pilot study with hypercholesterolemic children and adolescents, we investigated the effects of a combination of plant sterols, fish oil and B vitamins on the levels of four independent risk factors for CVD; LDL-cholesterol, triacylglycerols, C-reactive protein and homocysteine. METHODS: Twenty five participants (mean age 16 y, BMI 23 kg/m2) received daily for a period of 16 weeks an emulsified preparation comprising plant sterols esters (1300 mg), fish oil (providing 1000 mg eicosapentaenoic acid (EPA) plus docosahexaenoic acid (DHA)) and vitamins B12 (50 µg), B6 (2.5 mg), folic acid (800 µg) and coenzyme Q10 (3 mg). Atherogenic and inflammatory risk factors, plasma lipophilic vitamins, provitamins and fatty acids were measured at baseline, week 8 and 16. RESULTS: The serum total cholesterol, LDL- cholesterol, VLDL-cholesterol, subfractions LDL-2, IDL-1, IDL-2 and plasma homocysteine levels were significantly reduced at the end of the intervention period (p<0.05). The triacylglycerols levels decreased by 17.6%, but did not reach significance. No significant changes in high sensitivity C-reactive protein, HDL-cholesterol and apolipoprotein A-1 were observed during the study period. After standardisation for LDL cholesterol, there were no significant changes in the levels of plasma γ-tocopherol, ß-carotene and retinol, except for reduction in α-tocopherol levels. The plasma levels of n-3 fatty acids increased significantly with the dietary supplementation (p<0.05). CONCLUSIONS: Daily intake of a combination of plant sterols, fish oil and B vitamins may modulate the lipid profile of hypercholesterolemic children and adolescents. TRIAL REGISTRATION: Current Controlled Trials ISRCTN89549017.


Assuntos
Doenças Cardiovasculares/prevenção & controle , Óleos de Peixe/administração & dosagem , Hipercolesterolemia/prevenção & controle , Fitosteróis/administração & dosagem , Complexo Vitamínico B/administração & dosagem , Adolescente , Apolipoproteína A-I/sangue , Proteína C-Reativa/análise , Criança , HDL-Colesterol/sangue , LDL-Colesterol/sangue , Ácidos Graxos Ômega-3/sangue , Feminino , Humanos , Masculino , Projetos Piloto , Fatores de Risco , Triglicerídeos/sangue , Adulto Jovem , beta Caroteno/sangue , gama-Tocoferol/sangue
6.
Mol Nutr Food Res ; 67(14): e2200716, 2023 07.
Artigo em Inglês | MEDLINE | ID: mdl-37150886

RESUMO

SCOPE: A prospective study of 34492 participants shows an inverse association between (+)-catechin intake and coronary heart disease. The effects of (+)-catechin on atherosclerosis and associated risk factors are poorly understood and are investigated. METHODS AND RESULTS: (+)-Catechin attenuates reactive oxygen species production in human macrophages, endothelial cells and vascular smooth muscle cells, chemokine-driven monocytic migration, and proliferation of human macrophages and their expression of several pro-atherogenic genes. (+)-Catechin also improves oxidized LDL-mediated mitochondrial membrane depolarization in endothelial cells and attenuates growth factor-induced smooth muscle cell migration. In C57BL/6J mice fed high fat diet (HFD) for 3 weeks, (+)-catechin attenuates plasma levels of triacylglycerol and interleukin (IL)-1ß and IL-2, produces anti-atherogenic changes in liver gene expression, and reduces levels of white blood cells, myeloid-derived suppressor cells, Lin- Sca+ c-Kit+ cells, and common lymphoid progenitor cells within the bone marrow. In LDL receptor deficient mice fed HFD for 12 weeks, (+)-catechin attenuates atherosclerotic plaque burden and inflammation with reduced macrophage content and increased markers of plaque stability; smooth muscle cell and collagen content. CONCLUSION: This study provides novel, detailed insights into the cardio-protective actions of (+)-catechin together with underlying molecular mechanisms and supports further assessments of its beneficial effects in human trials.


Assuntos
Aterosclerose , Catequina , Placa Aterosclerótica , Humanos , Camundongos , Animais , Placa Aterosclerótica/metabolismo , Catequina/farmacologia , Catequina/metabolismo , Células Endoteliais/metabolismo , Camundongos Endogâmicos C57BL , Estudos Prospectivos , Camundongos Knockout , Aterosclerose/metabolismo , Inflamação/metabolismo , Receptores de LDL/metabolismo , Fatores de Risco
7.
Br J Nutr ; 108(4): 755-8, 2012 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-22313587

RESUMO

Long-chain fatty acids have been shown to suppress appetite and reduce energy intake (EI) by stimulating the release of gastrointestinal hormones such as cholecystokinin (CCK). The effect of NEFA acyl chain length on these parameters is not comprehensively understood. An in vitro screen tested the capacity of individual NEFA (C12 to C22) to trigger CCK release. There was a gradient in CCK release with increasing chain length. DHA (C22) stimulated significantly (P < 0.01) more CCK release than all other NEFA tested. Subsequently, we conducted a randomised, controlled, crossover intervention study using healthy males (n 18). The effects of no treatment (NT) and oral doses of emulsified DHA-rich (DHA) and oleic acid (OA)-rich oils were compared using 24 h EI as the primary endpoint. Participants reported significantly (P = 0.039) lower total daily EI (29 % reduction) with DHA compared to NT. There were no differences between DHA compared to OA and OA compared to NT. There was no between-treatment difference in the time to, or EI of, the first post-intervention eating occasion. It is concluded that NEFA stimulate CCK release in a chain length-dependent manner up to C22. These effects may be extended to the in vivo setting, as a DHA-based emulsion significantly reduced short-term EI.


Assuntos
Depressores do Apetite/metabolismo , Colecistocinina/metabolismo , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/metabolismo , Ingestão de Energia , Células Enteroendócrinas/metabolismo , Ácidos Graxos não Esterificados/metabolismo , Adulto , Depressores do Apetite/química , Linhagem Celular Tumoral , Estudos Cross-Over , Ácidos Docosa-Hexaenoicos/química , Emulsões , Ácidos Graxos não Esterificados/química , Humanos , Masculino , Pessoa de Meia-Idade , Peso Molecular , Método Simples-Cego , Adulto Jovem
8.
Front Neurosci ; 16: 843105, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35685773

RESUMO

Brain degenerative disorders such as Alzheimer's disease (AD) can be exacerbated by aberrant metabolism. Supplementation with probiotic bacteria is emerging as a promising preventative strategy for both neurodegeneration and metabolic syndrome. In this study, we assess the impact of the Lab4b probiotic consortium on (i) cognitive and pathological markers of AD progression and (ii) metabolic status in 3xTg-AD mice subjected to metabolic challenge with a high fat diet. The group receiving the probiotic performed better in the novel object recognition test and displayed higher hippocampal neuronal spine density than the control group at the end of the 12 weeks intervention period. These changes were accompanied by differences in localised (brain) and systemic anti-inflammatory responses that favoured the Probiotic group together with the prevention of diet induced weight gain and hypercholesterolaemia and the modulation of liver function. Compositional differences between the faecal microbiotas of the study groups included a lower Firmicutes:Bacteroidetes ratio and less numbers of viable yeast in the Probiotic group compared to the Control. The results illustrate the potential of the Lab4b probiotic as a neuroprotective agent and encourage further studies with human participants.

9.
Mol Nutr Food Res ; 65(17): e2100214, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34216185

RESUMO

SCOPE: Previous studies show that Lab4 probiotic consortium plus Lactobacillus plantarum CUL66 (Lab4P) reduces diet-induced weight gain and plasma cholesterol levels in C57BL/6J mice fed a high fat diet (HFD). The effect of Lab4P on atherosclerosis is not known and is therefore investigated. METHODS AND RESULTS: Atherosclerosis-associated parameters are analyzed in LDL receptor deficient mice fed HFD for 12 weeks alone or supplemented with Lab4P. Lab4P increases plasma HDL and triglyceride levels and decreases LDL/VLDL levels. Lab4P also reduces plaque burden and content of lipids and macrophages, indicative of dampened inflammation, and increases smooth muscle cell content, a marker of plaque stabilization. Atherosclerosis arrays show that Lab4P alters the liver expression of 19 key disease-associated genes. Lab4P also decreases the frequency of macrophages and T-cells in the bone marrow. In vitro assays using conditioned media from probiotic bacteria demonstrates attenuation of several atherosclerosis-associated processes in vitro such as chemokine-driven monocytic migration, proliferation of monocytes and macrophages, foam cell formation and associated changes in expression of key genes, and proliferation and migration of vascular smooth muscle cells. CONCLUSION: This study provides new insights into the anti-atherogenic actions of Lab4P together with the underlying mechanisms and supports further assessments in human trials.


Assuntos
Aterosclerose/terapia , Fígado/fisiologia , Placa Aterosclerótica/terapia , Probióticos/farmacologia , Animais , Aterosclerose/genética , Aterosclerose/patologia , Células da Medula Óssea , Colesterol/sangue , Meios de Cultivo Condicionados/farmacologia , Dieta Hiperlipídica/efeitos adversos , Regulação da Expressão Gênica , Lactobacillus plantarum , Lipídeos/sangue , Masculino , Camundongos Mutantes , Tamanho do Órgão , Placa Aterosclerótica/patologia , Receptores de LDL/genética , Baço/crescimento & desenvolvimento
10.
Front Nutr ; 8: 778289, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34901123

RESUMO

The anti-inflammatory and cholesterol lowering capabilities of probiotic bacteria highlight them as potential prophylactics against chronic inflammatory diseases, particularly cardiovascular disease. Previous studies in silico, in vitro, and in vivo suggest that the Lab4 probiotic consortium may harbour such capabilities and in the current study, we assessed plasma levels of cytokines/chemokines, short chain fatty acids and lipids and faecal levels of bile acids in a subpopulation of healthy Wistar rats included in 90-day repeat dose oral toxicity study. In the rats receiving Lab4, circulating levels of pro-inflammatory interleukin-6, tumour necrosis factor-α and keratinocyte chemoattractant/growth regulated oncogene were significantly lower compared to the control group demonstrating a systemic anti-inflammatory effect. These changes occurred alongside significant reductions in plasma low density lipoprotein cholesterol and increases in faecal bile acid excretion implying the ability to lower circulating cholesterol via the deconjugation of intestinal bile acids. Correlative analysis identified significant associations between plasma tumour necrosis factor-α and the plasma total cholesterol:high density lipoprotein cholesterol ratio and faecal levels of bifidobacteria in the Lab4 rats. Together, these data highlight Lab4 supplementation as a holistic approach to CVD prevention and encourages further studies in humans.

11.
Food Funct ; 12(8): 3657-3671, 2021 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-33900312

RESUMO

Atherosclerosis, an inflammatory disorder of the vasculature and the underlying cause of cardiovascular disease, is responsible for one in three global deaths. Consumption of active food ingredients such as omega-3 polyunsaturated fatty acids, flavanols and phytosterols has many beneficial effects on cardiovascular disease. However, their combined actions on the risk factors for atherosclerosis remains poorly understood. We have previously shown that a formulation containing each of these active components at physiologically relevant doses modulated several monocyte/macrophage processes associated with atherosclerosis in vitro, including inhibition of cytokine-induced pro-inflammatory gene expression, chemokine-driven monocyte migration, expression of M1 phenotype markers, and promotion of cholesterol efflux. The objectives of the present study were to investigate whether the protective actions of the formulation extended in vivo and to delineate the potential underlying mechanisms. The formulation produced several favourable changes, including higher plasma levels of HDL and reduced levels of macrophages and myeloid-derived suppressor cells in the bone marrow. The mRNA expression of liver-X-receptor-α, peroxisome proliferator-activated receptor-γ and superoxide dismutase-1 was induced in the liver and that of interferon-γ and the chemokine (C-X-C motif) ligand 1 decreased, thereby suggesting the potential mechanisms for many beneficial effects. Other changes were also observed such as increased plasma levels of triglycerides and lipid peroxidation that may reflect potential activation of brown fat. This study provides new insights into the protective actions and the potential underlying mechanisms of the formulation in vivo, particularly in relation to risk factors together with changes in systemic inflammation and hepatic lipid alterations associated with atherosclerosis and metabolic syndrome, and supports further assessments in human trials.


Assuntos
Cardiotônicos/farmacologia , Doença da Artéria Coronariana/prevenção & controle , Animais , Cardiotônicos/administração & dosagem , Dieta Hiperlipídica , Modelos Animais de Doenças , Ácidos Graxos Ômega-3/administração & dosagem , Flavanonas/administração & dosagem , Alimento Funcional , Expressão Gênica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Fitosteróis/administração & dosagem , Fatores de Risco
12.
Nutr J ; 6: 4, 2007 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-17254329

RESUMO

BACKGROUND: The health benefits of increased intakes of omega-3 fatty acids are well established but palatability often presents a problem. The process of emulsification is used in the food industry to provide a wider spectrum of use, often with the result of increased consumption. Moreover, as emulsification is an important step in the digestion and absorption of fats, the pre-emulsification process may enhance digestion and absorption. In this study the levels of plasma fatty acid and triacylglycerol (TAG) following the ingestion of either an oil mixture or an emulsified oil mixture have been compared. METHODS: In this randomised cross-over study, 13 volunteers received the oil mixture and 11 received the oil emulsion as part of an otherwise fat free meal. Blood samples were collected at 0, 1.5, 3, 4.5, 6, 7.5 and 9 hours after ingestion of oil, separated and stored at -20 degrees C. Plasma triacylglycerols were assessed spectrophotometrically and fatty acids were determined by gas chromatography. Following a washout period of twenty days the procedure was repeated with the assignments reversed. RESULTS: The postprandial plasma TAG and the C18:3 (n-6), C18:3(n-3), C20:5(n-3) and C22:6 (n-3) polyunsaturated fatty acid (PUFA) levels for the emulsified oil group were increased significantly (P = 0.0182; P = 0.0493; P = 0.0137; P < 0.0001; P = 0.0355 respectively) compared with the non-emulsified oil group. The C16:0 and C18:0 saturated fatty acids, the C18:1 (n-9) monounsaturated fatty acid and the C18:2 PUFA were not significantly different for the oil and emulsified oil groups. CONCLUSION: Pre-emulsification of an oil mixture prior to ingestion increases the absorption of longer chain more highly unsaturated fatty acids (especially eicosapentaenoic acid and docosahexaenoic acid) but does not affect absorption of shorter chain less saturated fatty acids, suggesting that pre-emulsification of fish oils may be a useful means of boosting absorption of these beneficial fatty acids.


Assuntos
Ácidos Graxos Ômega-3/farmacocinética , Adulto , Estudos Cross-Over , Dieta , Emulsões/farmacocinética , Jejum , Ácidos Graxos/sangue , Ácidos Graxos Insaturados/sangue , Feminino , Óleos de Peixe/farmacocinética , Alimentos , Humanos , Óleo de Semente do Linho/farmacocinética , Masculino , Pessoa de Meia-Idade , Óleos de Plantas/farmacocinética , Triglicerídeos/sangue , Ácido gama-Linolênico/farmacocinética
13.
Cartilage ; 7(1): 70-81, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26958319

RESUMO

OBJECTIVE: Glucosamine hydrochloride (GH) and chondroitin sulfate (CS) are commonly used for the treatment of osteoarthritis (OA). The aim of this study was to assess their effects, alone and in combination, on preventing aggrecan degradation and inflammation in an in vitro model of OA. DESIGN: To test the effects of GH and/or CS as a preventative treatment, cartilage explants were pretreated with the compound(s) using concentrations that showed no detrimental effect on chondrocyte viability. Interleukin-1α (IL-1α) was added to induce cartilage degradation, supernatant and explants were analyzed for proteoglycan degradation products, aggrecanase mRNA expression and activity, and for the release of inflammatory markers. RESULTS: Following treatment with IL-1α, 2 mg/mL dose of GH pretreatment was associated with a reduction of glycosaminoglycan release, reduced generation of the pathological interglobular domain aggrecan catabolites, decreased mRNA levels of ADAMTS-4 and -5 and reduced activity of ADAMTS-4. In contrast, CS alone did not have a significant effect on IL-1α-induced cartilage degradation and the addition of 0.4 mg/mL CS to 2 mg/mL GH did not further inhibit IL-1α-induced activity. Pretreatment with 2 mg/mL GH also reduced the release of inflammatory markers, prostaglandin E2 and nitric oxide induced by IL-1α while CS did not have a significant effect. CONCLUSIONS: The results suggest that GH prevents cartilage degradation mediated by aggrecanases ADAMTS-4 and -5, and may also reduce inflammation. This could be part of the mechanisms by which GH is effective in maintaining joint integrity and function, and preventing or delaying early symptoms of OA.

14.
PLoS One ; 11(3): e0151057, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-26950833

RESUMO

INTRODUCTION: Atherosclerosis is the underlying cause of cardiovascular disease that leads to more global mortalities each year than any other ailment. Consumption of active food ingredients such as phytosterols, omega-3 polyunsaturated fatty acids and flavanols are known to impart beneficial effects on cardiovascular disease although the combined actions of such agents in atherosclerosis is poorly understood. The aim of this study was to screen a nutritional supplement containing each of these active components for its anti-atherosclerotic effect on macrophages in vitro. RESULTS: The supplement attenuated the expression of intercellular adhesion molecule-1 and macrophage chemoattractant protein-1 in human and murine macrophages at physiologically relevant doses. The migratory capacity of human monocytes was also hindered, possibly mediated by eicosapentaenoic acid and catechin, while the ability of foam cells to efflux cholesterol was improved. The polarisation of murine macrophages towards a pro-inflammatory phenotype was also attenuated by the supplement. CONCLUSION: The formulation was able to hinder multiple key steps of atherosclerosis development in vitro by inhibiting monocyte recruitment, foam cell formation and macrophage polarisation towards an inflammatory phenotype. This is the first time a combination these ingredients has been shown to elicit such effects and supports its further study in preclinical in vivo models.


Assuntos
Aterosclerose/prevenção & controle , Suplementos Nutricionais , Ácidos Graxos Ômega-3/farmacologia , Flavonóis/farmacologia , Fitosteróis/farmacologia , Animais , Aterosclerose/genética , Aterosclerose/metabolismo , Aterosclerose/patologia , Transporte Biológico/efeitos dos fármacos , Linhagem Celular Tumoral , Movimento Celular/efeitos dos fármacos , Quimiocina CCL2/genética , Colesterol/metabolismo , Interações Medicamentosas , Regulação da Expressão Gênica/efeitos dos fármacos , Humanos , Molécula 1 de Adesão Intercelular/genética , Interferon gama/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Monócitos/citologia , Monócitos/efeitos dos fármacos , Fenótipo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
15.
BMJ Open Gastroenterol ; 2(1): e000052, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26719813

RESUMO

BACKGROUND: Vitamin D deficiency has been associated or implicated with the pathophysiology of the gastrointestinal conditions inflammatory bowel disease and colorectal cancer, as well as with depression. No trials or epidemiology studies to date have investigated a link with irritable bowel syndrome (IBS). A single case report has suggested a benefit in IBS of vitamin D supplementation. We hypothesised that IBS participants with vitamin D insufficiency would benefit from repletion in terms of their IBS symptoms. We undertook a pilot trial to provide data to support a power calculation and to justify a full trial. METHODS: This was a randomised, double blinded, three-arm parallel design trial of vitamin D, placebo or a combination of vitamin D and probiotics. Participants were further stratified according to whether they were vitamin D replete or insufficient. Vitamin D status was determined by blood test at baseline and exit; IBS symptoms were assessed by validated questionnaire; dietary intakes were assessed by food frequency questionnaire. RESULTS: A significant proportion of the IBS population were vitamin D deficient, such that the replete stratum could not be adequately recruited. There was a significant association in the baseline data between circulating vitamin D level and quality of life ("How much has IBS affected your life?"). Supplementation significantly improved vitamin D level versus placebo. IBS symptoms were not significantly improved in this pilot, although a power calculation was enabled from the intervention data. CONCLUSIONS: The IBS population exhibits significant levels of vitamin D insufficiency and would benefit from screening and possible supplementation. The impact of IBS on quality of life may be reduced by vitamin D level. Future trials should have a sample size of over 97. TRIAL REGISTRATION NUMBER: ICTRN 6116003917.

16.
Nutr Res ; 34(1): 17-24, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24418242

RESUMO

Longer-chain polyunsaturated fatty acids may have greater appetite-suppressing effects than shorter-chain, monosaturated, and saturated fatty acids. Because fish oils are predominantly composed of n-3 long-chain polyunsaturated fatty acid and may assist in the treatment of obesity comorbidities, their effect on body weight and body mass index is of interest. We hypothesized that daily supplementation with docosahexaenoic acid (DHA)-rich oil would reduce energy intake and body weight in overweight and obese women compared with supplementation with oleic acid (OA) rich oil. A double-blinded, randomized, parallel intervention was conducted. Body mass index (in kilograms per meter squared), body weight (in kilograms), body fat (in percent), and lean tissue (in kilograms) were measured at baseline and 12 weeks after intervention with DHA or OA. Diet diaries were also completed at these time points for estimation of energy and macronutrient intake. Subjects reported significantly lower energy (P = .020), carbohydrate (g) (P = .037), and fat (g) (P = .045) intake after DHA compared with OA. Body mass or composition was not affected by treatment, although a fall in body weight in the DHA group approached statistical significance (P = .089). Daily ingestion of DHA over a 12-week period may reduce energy intake in overweight and obese females, but longer-term and adequately powered studies using subjects of both sexes are needed. Other factors that should be considered include the following: the choice of control, the body mass index category of subjects, and ways of improving the compliancy and accuracy of dietary assessment.


Assuntos
Peso Corporal , Ingestão de Energia , Ácidos Graxos Insaturados/administração & dosagem , Obesidade/terapia , Sobrepeso/terapia , Adulto , Composição Corporal , Índice de Massa Corporal , Carboidratos da Dieta/administração & dosagem , Gorduras na Dieta/administração & dosagem , Suplementos Nutricionais , Ácidos Docosa-Hexaenoicos/administração & dosagem , Método Duplo-Cego , Emulsões/administração & dosagem , Feminino , Óleos de Peixe/administração & dosagem , Humanos , Pessoa de Meia-Idade , Ácido Oleico/administração & dosagem
17.
PLoS One ; 8(7): e67912, 2013.
Artigo em Inglês | MEDLINE | ID: mdl-23874465

RESUMO

BACKGROUND: The vulnerability of clinical trials to volunteer bias is under-reported. Volunteer bias is systematic error due to differences between those who choose to participate in studies and those who do not. METHODS AND RESULTS: This paper extends the applications of the concept of volunteer bias by using data from a trial of probiotic supplementation for childhood atopy in healthy dyads to explore 1) differences between a) trial participants and aggregated data from publicly available databases b) participants and non-participants as the trial progressed 2) impact on trial findings of weighting data according to deprivation (Townsend) fifths in the sample and target populations. 1) a) Recruits (n = 454) were less deprived than the target population, matched for area of residence and delivery dates (n = 6,893) (mean [SD] deprivation scores 0.09[4.21] and 0.79[4.08], t = 3.44, df = 511, p<0.001). b) i) As the trial progressed, representation of the most deprived decreased. These participants and smokers were less likely to be retained at 6 months (n = 430[95%]) (OR 0.29,0.13-0.67 and 0.20,0.09-0.46), and 2 years (n = 380[84%]) (aOR 0.68,0.50-0.93 and 0.55,0.28-1.09), and consent to infant blood sample donation (n = 220[48%]) (aOR 0.72,0.57-0.92 and 0.43,0.22-0.83). ii) Mothers interested in probiotics or research or reporting infants' adverse events or rashes were more likely to attend research clinics and consent to skin-prick testing. Mothers participating to help children were more likely to consent to infant blood sample donation. 2) In one trial outcome, atopic eczema, the intervention had a positive effect only in the over-represented, least deprived group. Here, data weighting attenuated risk reduction from 6.9%(0.9-13.1%) to 4.6%(-1.4-+10.5%), and OR from 0.40(0.18-0.91) to 0.56(0.26-1.21). Other findings were unchanged. CONCLUSIONS: Potential for volunteer bias intensified during the trial, due to non-participation of the most deprived and smokers. However, these were not the only predictors of non-participation. Data weighting quantified volunteer bias and modified one important trial outcome. TRIAL REGISTRATION: This randomised, double blind, parallel group, placebo controlled trial is registered with the International Standard Randomised Controlled Trials Register, Number (ISRCTN) 26287422. Registered title: Probiotics in the prevention of atopy in infants and children.


Assuntos
Ensaios Clínicos Controlados Aleatórios como Assunto , Projetos de Pesquisa , Viés de Seleção , Voluntários , Adulto , Pré-Escolar , Feminino , Humanos , Lactente , Estudos Longitudinais , Masculino , Mães , Avaliação de Processos e Resultados em Cuidados de Saúde , Fatores de Risco
18.
J Proteomics ; 75(10): 2916-23, 2012 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-22200674

RESUMO

Current measurement of appetite depends upon tools that are either subjective (visual analogue scales), or invasive (blood). Saliva is increasingly recognised as a valuable resource for biomarker analysis. Proteomics workflows may provide alternative means for the assessment of appetitive response. The study aimed to assess the potential value of the salivary proteome to detect novel biomarkers of appetite using an iTRAQ-based workflow. Diurnal variation of salivary protein concentrations was assessed. A randomised, controlled, crossover study examined the effects on the salivary proteome of isocaloric doses of various long chain fatty acid (LCFA) oil emulsions compared to no treatment (NT). Fasted males provided saliva samples before and following NT or dosing with LCFA emulsions. The oil component of the DHA emulsion contained predominantly docosahexaenoic acid and the oil component of OA contained predominantly oleic acid. Several proteins were present in significantly (p<0.05) different quantities in saliva samples taken following treatments compared to fasting samples. DHA caused alterations in thioredoxin and serpin B4 relative to OA and NT. A further study evaluated energy intake (EI) in response to LCFA in conjunction with subjective appetite scoring. DHA was associated with significantly lower EI relative to NT and OA (p=0.039). The collective data suggest investigation of salivary proteome may be of value in appetitive response. This article is part of a Special Issue entitled: Proteomics: The clinical link.


Assuntos
Apetite/fisiologia , Proteoma/metabolismo , Saliva/metabolismo , Biologia de Sistemas/métodos , Apetite/efeitos dos fármacos , Biomarcadores/análise , Biomarcadores/metabolismo , Compreensão , Estudos Cross-Over , Dieta , Gorduras na Dieta/farmacologia , Ingestão de Alimentos/efeitos dos fármacos , Ingestão de Alimentos/fisiologia , Jejum/metabolismo , Jejum/fisiologia , Ácidos Graxos/farmacologia , Humanos , Masculino , Proteoma/análise , Proteômica , Saliva/química , Proteínas e Peptídeos Salivares/análise , Proteínas e Peptídeos Salivares/metabolismo , Método Simples-Cego
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