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1.
Redox Biol ; 67: 102878, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37703668

RESUMO

Cruciferous-rich diets, particularly broccoli, have been associated with reduced risk of developing cancers of various sites, cardiovascular disease and type-2 diabetes. Sulforaphane (SF), a sulfur-containing broccoli-derived metabolite, has been identified as the major bioactive compound mediating these health benefits. Sulforaphane is a potent dietary activator of the transcription factor Nuclear factor erythroid-like 2 (NRF2), the master regulator of antioxidant cell capacity responsible for inducing cytoprotective genes, but its role in glucose homeostasis remains unclear. In this study, we set to test the hypothesis that SF regulates glucose metabolism and ameliorates glucose overload and its resulting oxidative stress by inducing NRF2 in human hepatoma HepG2 cells. HepG2 cells were exposed to varying glucose concentrations: basal (5.5 mM) and high glucose (25 mM), in the presence of physiological concentrations of SF (10 µM). SF upregulated the expression of glutathione (GSH) biosynthetic genes and significantly increased levels of reduced GSH. Labelled glucose and glutamine experiments to measure metabolic fluxes identified that SF increased intracellular utilisation of glycine and glutamate by redirecting the latter away from the TCA cycle and increased the import of cysteine from the media, likely to support glutathione synthesis. Furthermore, SF altered pathways generating NADPH, the necessary cofactor for oxidoreductase reactions, namely pentose phosphate pathway and 1C-metabolism, leading to the redirection of glucose away from glycolysis and towards PPP and of methionine towards methylation substrates. Finally, transcriptomic and targeted metabolomics LC-MS analysis of NRF2-KD HepG2 cells generated using CRISPR-Cas9 genome editing revealed that the above metabolic effects are mediated through NRF2. These results suggest that the antioxidant properties of cruciferous diets are intricately connected to their metabolic benefits.


Assuntos
Antioxidantes , Fator 2 Relacionado a NF-E2 , Humanos , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Fator 2 Relacionado a NF-E2/genética , Fator 2 Relacionado a NF-E2/metabolismo , Isotiocianatos/farmacologia , Estresse Oxidativo , Glutationa/metabolismo , Homeostase , Glucose
2.
Heliyon ; 9(7): e17900, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37539217

RESUMO

Since its inception in December 2019, many safe and effective vaccines have been invented and approved for use against COVID-19 along with various non-pharmaceutical interventions. But the emergence of numerous SARS-CoV-2 variants has put the effectiveness of these vaccines, and other intervention measures under threat. So it is important to understand the dynamics of COVID-19 in the presence of its variants of concern (VOC) in controlling the spread of the disease. To address these situations and to find a way out of this problem, a new mathematical model consisting of a system of non-linear differential equations considering the original COVID-19 strain with its two variants of concern (Delta and Omicron) has been proposed and formulated in this paper. We then analyzed the proposed model to study the transmission dynamics of this multi-strain model and to investigate the consequences of the emergence of multiple new SARS-CoV-2 variants which are more transmissible than the previous ones. The control reproduction number, an important threshold parameter, is then calculated using the next-generation matrix method. Further, we presented the discussion about the stability of the model equilibrium. It is shown that the disease-free equilibrium (DFE) of the model is locally asymptotic stable when the control reproduction is less than unity. It is also shown that the model has a unique endemic equilibrium (EEP) which is locally asymptotic stable when the control reproduction number is greater than unity. Using the Center Manifold theory it is shown that the model also exhibits the backward bifurcation phenomenon when the control reproduction number is less than unity. Again without considering the re-infection of the recovered individuals, it is proved that the disease-free equilibrium is globally asymptotically stable when the reproduction threshold is less than unity. Finally, numerical simulations are performed to verify the analytic results and to show the impact of multiple new SARS-CoV-2 variants in the population which are more contagious than the previous variants. Global uncertainty and sensitivity analysis has been done to identify which parameters have a greater impact on disease dynamics and control disease transmission. Numerical simulation suggests that the emergence of new variants of concern increases COVID-19 infection and related deaths. It also reveals that a combination of non-pharmaceutical interventions with vaccination programs of new more effective vaccines should be continued to control the disease outbreak. This study also suggests that more doses of vaccine should provide to combat new and deadly variants like Delta and Omicron.

3.
Foods ; 12(5)2023 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-36900469

RESUMO

White mugwort (Artemisia lactiflora Wall.), a traditional Chinese medicine, has been widely consumed in different forms for health care purposes. In this study, the in vitro digestion model of INFOGEST was used to investigate the bioaccessibility, stability, and antioxidant activity of polyphenols from two different forms of white mugwort, including dried powder (P 50, 100, and 150 mg/mL) and fresh extract (FE 5, 15, and 30 mg/mL). During digestion, the bioaccessibility of TPC and antioxidant activity were influenced by the form and ingested concentration of white mugwort. The highest bioaccessibility of the total phenolic content (TPC) and relative antioxidant activity were found at the lowest P and FE concentrations, as calculated relative to the TPC and antioxidant activity of P-MetOH and FE-MetOH based on the dry weight of the sample. Post-digestion, in comparison to P, FE had higher bioaccessibility (FE = 287.7% and P = 130.7%), relative DPPH radical scavenging activity (FE = 104.2% and P = 47.3%), and relative FRAP (FE = 673.5% and P = 66.5%). Nine compounds, 3-caffeoylquinic acid, 5-caffeoylquinic acid, 3,5-di-caffeoylquinic acid, sinapolymalate, isovitexin, kaempferol, morin, rutin, and quercetin, identified in both samples were modified during digestion, yet still provided strong antioxidant activity. These findings suggest that white mugwort extract possesses a higher polyphenol bioaccessibility, showing great potential as a functional ingredient.

4.
Am J Clin Nutr ; 117(3): 477-489, 2023 03.
Artigo em Inglês | MEDLINE | ID: mdl-36811474

RESUMO

BACKGROUND: Dietary intake of pulses is associated with beneficial effects on body weight management and cardiometabolic health, but some of these effects are now known to depend on integrity of plant cells, which are usually disrupted by flour milling. Novel cellular flours preserve the intrinsic dietary fiber structure of whole pulses and provide a way to enrich preprocessed foods with encapsulated macronutrients. OBJECTIVES: This study aimed to determine the effects of replacing wheat flour with cellular chickpea flour on postprandial gut hormones, glucose, insulin, and satiety responses to white bread. METHODS: We conducted a double-blind randomized crossover study in which postprandial blood samples and scores were collected from healthy human participants (n = 20) after they consumed bread enriched with 0%, 30%, or 60% (wt/wt) cellular chickpea powder (CCP, 50 g total starch per serving). RESULTS: Bread type significantly affected postprandial glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) responses (time × treatment, P = 0.001 for both). The 60% CCP breads elicited significantly elevated and sustained release of these anorexigenic hormones [between 0% and 60% CPP-GLP-1: mean difference incremental area under the curve (iAUC), 3101 pM/min; 95% CI: 1891, 4310; P-adjusted < 0.001; PYY: mean difference iAUC, 3576 pM/min; 95% CI: 1024, 6128; P-adjusted = 0.006] and tended to increase fullness (time × treatment, P = 0.053). Moreover, bread type significantly influenced glycemia and insulinemia (time × treatment, P < 0.001, P = 0.006, and P = 0.001 for glucose, insulin, and C-peptide, respectively), with 30% CCP breads eliciting a >40% lower glucose iAUC (P-adjusted < 0.001) than the 0% CCP bread. Our in vitro studies revealed slow digestion of intact chickpea cells and provide a mechanistic explanation for the physiologic effects. CONCLUSIONS: The novel use of intact chickpea cells to replace refined flours in a white bread stimulates an anorexigenic gut hormone response and has potential to improve dietary strategies for prevention and treatment of cardiometabolic diseases. This study was registered at clinicaltrials.gov as NCT03994276.


Assuntos
Doenças Cardiovasculares , Cicer , Hormônios Gastrointestinais , Humanos , Pão , Farinha , Estudos Cross-Over , Glicemia , Triticum/química , Glucose , Peptídeo 1 Semelhante ao Glucagon , Insulina , Peptídeo YY , Período Pós-Prandial
5.
Food Chem ; 404(Pt A): 134538, 2023 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-36257266

RESUMO

The cell structure and low glycaemic benefits of pulses are compromised by conventional flour-milling. Cellular chickpea powders ('CCPs') are a new alternative to pulse flours. Here we investigated the in vitro bioaccessibility of essential amino acids ('EAAs') from CCP-enriched bread products and determined the effect of their consumption on serum amino acid responses in healthy humans (n = 20, randomised cross-over design). Breads were prepared with 0, 30 and 60 % of the wheat flour replaced by CCP (intact cells containing encapsulated protein). We found that significant proportion of EAAs from encapsulated protein became bioaccessible during in vitro duodenal digestion, and that in vivo serum EAA responses from healthy human participants were significantly higher following consumption of CCP-enriched breads. Furthermore, the EAA profile of in vitro digestion products were well-correlated with in vivo peak serum EAAs responses. We conclude that CCP-enrichment of wheat bread improved the amount and diversity of bioavailable EAAs.


Assuntos
Pão , Farinha , Humanos , Aminoácidos , Digestão , Células Vegetais , Triticum/química , Estudos Cross-Over
6.
Int J Mol Sci ; 23(22)2022 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-36430154

RESUMO

The gut is a selective barrier that not only allows the translocation of nutrients from food, but also microbe-derived metabolites to the systemic circulation that flows through the liver. Microbiota dysbiosis occurs when energy imbalances appear due to an unhealthy diet and a sedentary lifestyle. Dysbiosis has a critical impact on increasing intestinal permeability and epithelial barrier deterioration, contributing to bacterial and antigen translocation to the liver, triggering non-alcoholic fatty liver disease (NAFLD) progression. In this study, the potential therapeutic/beneficial effects of a combination of metabolic cofactors (a multi-ingredient; MI) (betaine, N-acetylcysteine, L-carnitine, and nicotinamide riboside) against NAFLD were evaluated. In addition, we investigated the effects of this metabolic cofactors' combination as a modulator of other players of the gut-liver axis during the disease, including gut barrier dysfunction and microbiota dysbiosis. Diet-induced NAFLD mice were distributed into two groups, treated with the vehicle (NAFLD group) or with a combination of metabolic cofactors (NAFLD-MI group), and small intestines were harvested from all animals for histological, molecular, and omics analysis. The MI treatment ameliorated gut morphological changes, decreased gut barrier permeability, and reduced gene expression of some proinflammatory cytokines. Moreover, epithelial cell proliferation and the number of goblet cells were increased after MI supplementation. In addition, supplementation with the MI combination promoted changes in the intestinal microbiota composition and diversity, as well as modulating short-chain fatty acids (SCFAs) concentrations in feces. Taken together, this specific combination of metabolic cofactors can reverse gut barrier disruption and microbiota dysbiosis contributing to the amelioration of NAFLD progression by modulating key players of the gut-liver axis.


Assuntos
Microbioma Gastrointestinal , Hepatopatia Gordurosa não Alcoólica , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/metabolismo , Disbiose , Ácidos Graxos Voláteis/farmacologia
7.
Infect Dis Model ; 7(4): 660-689, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36276578

RESUMO

In this paper, a deterministic compartmental model is presented to assess the impact of vaccination and non-pharmaceutical interventions (social distance, awareness, face mask, and quarantine) on the transmission dynamics of COVID-19 with co-morbidity and re-infection. An expression for the basic reproduction number is then derived for this model. Theoretical analysis shows that the model exhibits backward bifurcation phenomenon when the basic reproduction number is less than unity. But for the case of no re-infection, the model has a globally asymptotically stable disease-free equilibrium (DFE) when the basic reproduction number is less than unity. Furthermore, it is shown that in the case of no re-infection, a unique endemic equilibrium point (EEP) of the model exists which is globally asymptotically stable whenever the reproduction number is greater than unity. From the global sensitivity and uncertainty analysis, we have identified mask coverage, mask efficacy, vaccine coverage, vaccine efficacy, and contact rate as the most influential parameters influencing the spread of COVID-19. Numerical simulation results show that the use of effective vaccines with proper implementation of non-pharmaceutical interventions could lead to the elimination of COVID-19 from the community. Numerical simulations also suggest that the control strategy that ensures a continuous and effective mass vaccination program is the most cost-effective control strategy. The study also shows that in the presence of any co-morbidity and with the occurrence of re-infection, the disease burden may increase.

8.
Molecules ; 27(17)2022 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-36080136

RESUMO

BACKGROUND: The consumption of foods rich in anthocyanins (ACN) have been associated with beneficial properties in chronic inflammatory disorders such as intestinal bowel diseases (IBD). These effects were attributed not only to a direct antioxidant mechanism but also to the modulation of cell redox-dependent signaling. However, ACN bioavailability is low for their poor stability in the digestive tract, so ACN gastrointestinal digestion should be considered. METHODS: To have a more realistic knowledge of the effects of ACN, we performed an in vitro simulated gastrointestinal digestion of an ACN-rich purified and standardized bilberry and blackcurrant extract (BBE), followed by an evaluation of ACN composition modification (HPLC-DAD and pH differential method) and antioxidant activity (FRAP assay). Then, we studied the effects of BBE gastrointestinal extract on Caco-2 exposed to TNF-α. RESULTS: The results confirmed the high instability of ACN in the mild alkaline environment of the small intestine (17% recovery index). However, the digested BBE maintained part of its bioactivity. Additionally, BBE gastrointestinal extract inhibited the TNF-α-induced NF-κB pathway in Caco-2 and activated the Nrf2 pathway. CONCLUSIONS: Although ACN stability is affected by gastrointestinal digestion, the anti-inflammatory and antioxidant activity of digested extracts were confirmed; thus, the loss of ACN can probably be counterweighed by their metabolites. Then, ACN introduced by diet or food supplements could represent an approach for IBD prevention.


Assuntos
Doenças Inflamatórias Intestinais , Ribes , Antocianinas/metabolismo , Antocianinas/farmacologia , Anti-Inflamatórios/metabolismo , Anti-Inflamatórios/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Células CACO-2 , Células Epiteliais , Humanos , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/metabolismo , Extratos Vegetais/química , Ribes/metabolismo , Fator de Necrose Tumoral alfa/metabolismo
9.
Nutrients ; 14(16)2022 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-36014767

RESUMO

Diets rich in cruciferous vegetables have been associated with a lower risk of incidence and progression of prostate cancer. Sulforaphane, an isothiocyanate derived from 4-methylsulphinylbutyl glucosinolate (glucoraphanin) that accumulates in certain of these vegetables, notably broccoli, has been implicated in their protective effects. Likewise, the consumption of garlic and its sulphur-containing compounds such as alliin have been associated with a reduction in risk of prostate cancer. In this study, we tested whether consuming glucoraphanin derived from broccoli seeds and alliin derived from garlic resulted in the occurrence of these potential bioactive compounds in the prostate, which may contribute to our understanding of the putative protective effects of these dietary components. We recruited 42 men scheduled for a trans-perineal prostate biopsy into a randomised, double-blinded, 2 × 2-factorial dietary supplement four-week intervention study, and 39 completed the study. The two active interventions were supplements providing glucoraphanin from broccoli (BroccoMax®) and alliin from garlic (Kwai Heartcare®). Following the intervention, prostate biopsy tissue was analysed for the presence of sulforaphane and its thiol conjugates and for alliin and associated metabolites. Sulforaphane occurred in significantly higher levels in the prostate tissue (both within the transition and peripheral zone) of men consuming the glucoraphanin containing supplements (p < 0.0001) compared to men not consuming these supplements. However, while alliin and alliin-derived metabolites were detected within the prostate, there was no significant difference in the concentrations of these compounds in the prostate of men consuming supplements derived from garlic compared to men not consuming these supplements.


Assuntos
Allium , Brassica , Neoplasias da Próstata , Antioxidantes/metabolismo , Brassica/metabolismo , Cisteína/análogos & derivados , Glucosinolatos/metabolismo , Humanos , Imidoésteres/metabolismo , Isotiocianatos/metabolismo , Masculino , Próstata/metabolismo , Neoplasias da Próstata/metabolismo , Neoplasias da Próstata/prevenção & controle , Sulfóxidos
10.
Front Plant Sci ; 13: 855707, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35432397

RESUMO

Broccoli cultivars that have enhanced accumulation of methionine-derived glucosinolates have been developed through the introgression of a novel allele of the MYB28 transcription factor from the wild species Brassica villosa. Through a novel k-mer approach, we characterised the extent of the introgression of unique B. villosa genome sequences into high glucosinolate broccoli genotypes. RNAseq analyses indicated that the introgression of the B. villosa MYB28 C2 allele resulted in the enhanced expression of the MYB28 transcription factor, and modified expression of genes associated with sulphate absorption and reduction, and methionine and glucosinolate biosynthesis when compared to standard broccoli. A adenine-thymine (AT) short tandem repeat (STR) was identified within the 5' untranslated region (UTR) B. villosa MYB28 allele that was absent from two divergent cultivated forms of Brassica oleracea, which may underpin the enhanced expression of B. villosa MYB28.

11.
Invest Ophthalmol Vis Sci ; 62(15): 2, 2021 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-34854886

RESUMO

Purpose: Sulforaphane (SFN) is a therapeutic phytochemical agent for many health conditions. SFN-induced cytotoxicity is shown to have promise in preventing posterior capsule opacification (PCO). In the current study, we aimed to elucidate key processes and mechanisms linking SFN treatment to lens cell death. Methods: The human lens epithelial cell line FHL124 and central anterior epithelium were used as experimental models. Cell death was assessed by microscopic observation and cell damage/viability assays. Gene or protein levels were assessed by TaqMan RT-PCR or immunoblotting. Mitochondrial networks and DNA damage were assessed by immunofluorescence. Mitochondrial membrane potential, activating transcription factor 6 (ATF6) activity, ratio of reduced glutathione (GSH) to oxidized glutathione (GSSG), and glutathione reductase (GR) activity were measured using different light reporter assays. SFN metabolites were analyzed by LC-MS/MS. Results: Treatment with N-acetylcysteine (NAC), a reactive oxygen species scavenger, prevented SFN-induced cell death in both models. NAC also significantly protected FHL124 cells from SFN-induced mitochondrial dysfunctions, endoplasmic reticulum stress (ERS), DNA damage and autophagy. SFN significantly depleted GSH, the major antioxidant in the eye, and reduced GR activity, despite doubling its protein levels. The most abundant SFN conjugate detected in lens cells following SFN application was SFN-GSH. The addition of GSH protected lens cells from all SFN-induced cellular events. Conclusions: SFN depletes GSH levels in lens cells through conjugation and inhibition of GR activity. This leads to increased reactive oxygen species and oxidative stress that trigger mitochondrial dysfunction, ERS, autophagy, and DNA damage, leading to cell death. In summary, the work presented provides a mechanistic understanding to support the therapeutic application of SFN for PCO and other disorders.


Assuntos
Anticarcinógenos/farmacologia , Biomarcadores/metabolismo , Células Epiteliais/efeitos dos fármacos , Glutationa/metabolismo , Isotiocianatos/farmacologia , Cristalino/citologia , Sulfóxidos/farmacologia , Acetilcisteína/farmacologia , Fator 6 Ativador da Transcrição/metabolismo , Idoso , Idoso de 80 Anos ou mais , Apoptose/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular , Cromatografia Líquida , Células Epiteliais/metabolismo , Células Epiteliais/patologia , Sequestradores de Radicais Livres/farmacologia , Dissulfeto de Glutationa/metabolismo , Glutationa Redutase/metabolismo , Humanos , Immunoblotting , Potencial da Membrana Mitocondrial/fisiologia , Pessoa de Meia-Idade , Oxirredução , Espécies Reativas de Oxigênio/metabolismo , Reação em Cadeia da Polimerase em Tempo Real , Espectrometria de Massas em Tandem
12.
Molecules ; 26(21)2021 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-34770853

RESUMO

The gut microbiota is critical to the maintenance of physiological homeostasis and as such is implicated in a range of diseases such as colon cancer, ulcerative colitis, diabetes, cardiovascular diseases, and neurodegenerative diseases. Short chain fatty acids (SCFAs) are key metabolites produced by the gut microbiota from the fermentation of dietary fibre. Here we present a novel, sensitive, and direct LC-MS/MS technique using isotopically labelled internal standards without derivatisation for the analysis of SCFAs in different biological matrices. The technique has significant advantages over the current widely used techniques based on sample derivatization and GC-MS analysis, including fast and simple sample preparation and short LC runtime (10 min). The technique is specific and sensitive for the quantification of acetate, butyrate, isobutyrate, isovalerate, lactate, propionate and valerate. The limits of detection were all 0.001 mM except for acetate which was 0.003 mM. The calibration curves for all the analytes were linear with correlation coefficients r2 > 0.998. The intra- and inter-day precisions in three levels of known concentrations were <12% and <20%, respectively. The quantification accuracy ranged from 92% to 120%. The technique reported here offers a valuable analytical tool for use in studies of SCFA production in the gut and their distribution to host tissues.


Assuntos
Líquidos Corporais/química , Colo/química , Ácidos Graxos Voláteis/análise , Cromatografia Líquida/instrumentação , Desenho de Equipamento , Espectrometria de Massas em Tandem/instrumentação
13.
CRISPR J ; 4(3): 416-426, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34152214

RESUMO

Discoveries in model plants grown under optimal conditions can provide important directions for crop improvement. However, it is important to verify whether results can be translated to crop plants grown in the field. In this study, we sought to study the role of MYB28 in the regulation of aliphatic glucosinolate (A-GSL) biosynthesis and associated sulfur metabolism in field-grown Brassica oleracea with the use of Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR)-Cas9 gene-editing technology. We describe the first myb28 knockout mutant in B. oleracea, and the first CRISPR field trial in the United Kingdom approved and regulated by the UK Department for Environment, Food & Rural Affairs after the reclassification of gene-edited crops as genetically modified organisms by the European Court of Justice on July 25, 2018. We report that knocking out myb28 results in downregulation of A-GSL biosynthesis genes and reduction in accumulation of the methionine-derived glucosinolate, glucoraphanin, in leaves and florets of field-grown myb28 mutant broccoli plants, whereas accumulation of sulfate, S-methyl cysteine sulfoxide, and indole glucosinolate in leaf and floret tissues remained unchanged. These results demonstrate the potential of gene-editing approaches to translate discoveries in fundamental biological processes for improved crop performance.


Assuntos
Brassica/genética , Brassica/metabolismo , Sistemas CRISPR-Cas , Edição de Genes/métodos , Glucosinolatos/biossíntese , Glucosinolatos/genética , Histona Acetiltransferases/genética , Histona Acetiltransferases/metabolismo , Proteínas de Arabidopsis , Produtos Agrícolas/genética , Produtos Agrícolas/metabolismo , Expressão Gênica , Oximas , Plantas Geneticamente Modificadas , Sulfóxidos/metabolismo , Reino Unido
14.
Eur J Nutr ; 60(7): 3987-3999, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33934200

RESUMO

PURPOSE: Plasma trimethylamine-N-oxide (TMAO) levels have been shown to correlate with increased risk of metabolic diseases including cardiovascular diseases. TMAO exposure predominantly occurs as a consequence of gut microbiota-dependent trimethylamine (TMA) production from dietary substrates including choline, carnitine and betaine, which is then converted to TMAO in the liver. Reducing microbial TMA production is likely to be the most effective and sustainable approach to overcoming TMAO burden in humans. Current models for studying microbial TMA production have numerous weaknesses including the cost and length of human studies, differences in TMA(O) metabolism in animal models and the risk of failing to replicate multi-enzyme/multi-strain pathways when using isolated bacterial strains. The purpose of this research was to investigate TMA production from dietary precursors in an in-vitro model of the human colon. METHODS: TMA production from choline, L-carnitine, betaine and γ-butyrobetaine was studied over 24-48 h using an in-vitro human colon model with metabolite quantification performed using LC-MS. RESULTS: Choline was metabolised via the direct choline TMA-lyase route but not the indirect choline-betaine-TMA route, conversion of L-carnitine to TMA was slower than that of choline and involves the formation of the intermediate γ-BB, whereas the Rieske-type monooxygenase/reductase pathway for L-carnitine metabolism to TMA was negligible. The rate of TMA production from precursors was choline > carnitine > betaine > γ-BB. 3,3-Dimethyl-1-butanol (DMB) had no effect on the conversion of choline to TMA. CONCLUSION: The metabolic routes for microbial TMA production in the colon model are consistent with observations from human studies. Thus, this model is suitable for studying gut microbiota metabolism of TMA and for screening potential therapeutic targets that aim to attenuate TMA production by the gut microbiota. TRIAL REGISTRATION NUMBER: NCT02653001 ( http://www.clinicaltrials.gov ), registered 12 Jan 2016.


Assuntos
Microbioma Gastrointestinal , Animais , Carnitina , Colina , Colo , Fermentação , Humanos , Metilaminas
15.
J Anal Methods Chem ; 2020: 2359397, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32399306

RESUMO

Isoflavones and isoflavandiols have shown many health benefits, such as reducing cardiovascular disease, cancer, age-related disease, and osteoporosis. However, to investigate the relationships between consumption of isoflavones and their health benefits, it is important to be able to accurately quantify exposure in the large numbers of samples typically produced in association studies (i.e., several thousands). Current methods rely on solid-phase extraction protocols for sample cleanup, resulting in protracted extraction and analysis times. Here, we describe a fast and easy sample preparation method of human urine samples for subsequent quantification of daidzein, genistein (isoflavones), and equol (isoflavandiol) using LC-MS/MS. Sample preparation involves only the addition of dimethylformamide (DMF) and formic acid (FA) after enzymatic hydrolysis of their metabolites by a ß-glucuronidase and sulfatase mixture. The method was validated by precision, linearity, accuracy, recoveries, limit of detection (LOD), and limit of quantification (LOQ). Linear calibration curves have been shown by daidzein, genistein, and equol. The correlation coefficients values are r 2 > 0.99 for daidzein, genistein, and equol. LOD for daidzein and genistein was 1 ng/ml and equol was 2 ng/ml. Recoveries were >90%, and the relative standard deviation for intraday (<10%) and interday (≤20% over 10 days) was good. This method is suitable for quantification of isoflavones and the microbial metabolite equol in human urine and is particularly useful where large numbers of samples require analysis.

16.
Int J Syst Evol Microbiol ; 70(5): 3012-3017, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32228805

RESUMO

A novel Gram-positive, catalase negative, rod-shaped strain, FI11369T, was isolated from gari, a traditional West African fermented food derived from cassava. Based on 16S rRNA gene sequence similarity, the closest type strains were Lactobacillus xiangfangensis LMG 26013T (99.4 % similarity), Lactobacillus plajomi NBRC 107333T (99.1 %), Lactobacillus paraplantarum DSM 10667T (99.1 %), Lactobacillus pentosus DSM 20314T (99.0 %), Lactobacillus plantarum subsp. plantarum ATCC 14917T (99.0 %), Lactobacillus modestisalitolerans NBRC 107235T (98.9 %), Lactobacillus plantarum subsp. argentoratensis DSM 16365T (98.9 %) and Lactobacillus daowaiensis NCIMB 15183T (98.8 %). The genome of strain FI11369T was sequenced and the average nucleotide identity (ANI) was compared with its closest relatives. ANI analysis showed that the closest relative, L. xiangfangensis DSM 27103T, had only a 82.4 % similarity. The main fatty acids of FI11369T were saturated C16 : 0 (18.2 %), unsaturated C18 : 1 ω9c (43.8 %) and cyclopropane C19 : 0 cyclo (ω10c and/or ω6; 22.5 %). Based on the genotypic and phenotypic data obtained in this study, a novel Lactobacillus species, Lactobacillus garii sp. nov., with the type strain FI11369T (=NCIMB 15148=DSM 108249), is proposed.


Assuntos
Alimentos Fermentados/microbiologia , Microbiologia de Alimentos , Lactobacillus/classificação , Manihot/microbiologia , Filogenia , Técnicas de Tipagem Bacteriana , Composição de Bases , DNA Bacteriano/genética , Ácidos Graxos/química , Genes Bacterianos , Gana , Lactobacillus/isolamento & purificação , Hibridização de Ácido Nucleico , RNA Ribossômico 16S/genética , Análise de Sequência de DNA
17.
Food Chem ; 319: 126514, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32179369

RESUMO

Caseins and whey proteins are known as 'slow' and 'fast' proteins, respectively, based on their amino acid absorption rate. However, there is limited understanding of the mechanisms controlling their behaviour during gastro-intestinal transit. A protein model system (8% total protein) with varying casein:whey protein ratios (0:100, 20:80, 50:50 and 80:20) were subjected to in vitro gastro-intestinal digestion using a semi-dynamic gastric model, a static intestinal model and an ex vivo absorption model (Ussing chambers). The casein-rich (≥50%) samples showed the formation of solid coagula that were persistent throughout gastric digestion, which caused a delay in nutrient emptying, slower digestion and leucine absorption kinetics. In contrast, whey proteins formed more soluble aggregates during the gastric phase, which led to faster gastric emptying, rapid intestinal hydrolysis, and higher and faster leucine absorption. This work shows the key role of the gastric restructuring for the overall digestive mechanism and kinetics of food, in particular proteins.


Assuntos
Caseínas/química , Lipídeos/química , Proteínas do Soro do Leite/química , Animais , Digestão , Feminino , Esvaziamento Gástrico , Hidrólise , Leucina/química , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Estômago
18.
Mol Nutr Food Res ; 63(20): e1900461, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31410992

RESUMO

SCOPE: Observational studies have associated consumption of cruciferous vegetables with reduced risk of prostate cancer. This effect has been associated with the degradation products of glucosinolates-thioglycosides that accumulate within crucifers. The possible role of S-methyl cysteine sulfoxide, a metabolite that also accumulates in cruciferous vegetables, and its derivatives, in cancer prevention is relatively unexplored compared to glucosinolate derivatives. The hypothesis that consuming a broccoli soup results in the accumulation of sulfate (a SMCSO derivative) and other broccoli-derived metabolites in prostate tissue is tested. METHODS AND RESULTS: Eighteen men scheduled for transperineal prostate biopsy were recruited into a 4-week parallel single blinded diet supplementation study (NCT02821728). Nine men supplemented their diet with three 300 mL portions of a broccoli soup each week for four weeks prior to surgery. Analyses of prostate biopsy tissues reveal no detectable levels of glucosinolates and derivatives. In contrast, SMCSO is detected in prostate tissues of the participants, with significantly higher levels in tissue of men in the supplementation arm. SMCSO was also found in blood and urine samples from a previous intervention study with the identical broccoli soup. CONCLUSION: The consequences of SMCSO accumulation in prostate tissues and its potential role in prevention of prostate cancer remains to be investigated.


Assuntos
Brassica , Próstata/metabolismo , Sulfóxidos/metabolismo , Idoso , Allium , Suplementos Nutricionais , Glucosinolatos/metabolismo , Humanos , Imidoésteres/metabolismo , Isotiocianatos/metabolismo , Masculino , Pessoa de Meia-Idade , Oximas , Neoplasias da Próstata/patologia , Neoplasias da Próstata/prevenção & controle , Método Simples-Cego
19.
Molecules ; 24(13)2019 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-31269651

RESUMO

This is the first report describing an analytical method for quantitative analysis of two naturally occurring sulphur compounds, S-methyl-l-cysteine (SMC) and S-methyl-l-cysteine sulfoxide (SMCSO), in human body fluids using isotope-labelled internal standards and liquid chromatography-mass spectrometry (LC-MS)/MS techniques. This method was validated according to the guideline of the Royal Society of Chemistry Analytical Methods Committee. It offers significant advantages including simple and fast preparation of human biological samples. The limits of detection of SMC were 0.08 µM for urine and 0.04 µM for plasma. The limits of detection of SMCSO were 0.03 µM for urine and 0.02 µM for plasma. The calibration curves of all matrices showed linearity with correlation coefficients r2 > 0.9987. The intra and inter day precisions in three levels of known concentrations were >10% and >20%, respectively. The quantification accuracy was 98.28 ± 5.66%. The proposed method would be beneficial for the rapid and accurate determination of the SMC and SMCSO in human plasma and urine samples using by isotope labelled internal standards.


Assuntos
Cromatografia Líquida/métodos , Cisteína/análogos & derivados , Espectrometria de Massas em Tandem/métodos , Adolescente , Adulto , Idoso , Cisteína/sangue , Cisteína/síntese química , Cisteína/química , Cisteína/urina , Feminino , Humanos , Marcação por Isótopo , Masculino , Pessoa de Meia-Idade , Padrões de Referência , Reprodutibilidade dos Testes , Adulto Jovem
20.
Am J Clin Nutr ; 109(4): 1133-1144, 2019 04 01.
Artigo em Inglês | MEDLINE | ID: mdl-30982861

RESUMO

BACKGROUND: Epidemiological evidence suggests that consumption of cruciferous vegetables is associated with reduced risk of prostate cancer progression, largely attributed to the biological activity of glucosinolate degradation products, such as sulforaphane derived from glucoraphanin. Because there are few therapeutic interventions for men on active surveillance for prostate cancer to reduce the risk of cancer progression, dietary approaches are an appealing option for patients. OBJECTIVE: We evaluated whether consumption of a glucoraphanin-rich broccoli soup for 1 y leads to changes in gene expression in prostate tissue of men with localized prostate cancer. METHODS: Forty-nine men on active surveillance completed a 3-arm parallel randomized double-blinded intervention study for 12 mo and underwent transperineal template biopsy procedures and dietary assessment at the start and end of the study. Patients received a weekly 300 mL portion of soup made from a standard broccoli (control) or from 1 of 2 experimental broccoli genotypes with enhanced concentrations of glucoraphanin, delivering 3 and 7 times that of the control, respectively. Gene expression in tissues from each patient obtained before and after the dietary intervention was quantified by RNA sequencing followed by gene set enrichment analyses. RESULTS: In the control arm, there were several hundred changes in gene expression in nonneoplastic tissue during the 12 mo. These were associated with an increase in expression of potentially oncogenic pathways including inflammation processes and epithelial-mesenchymal transition. Changes in gene expression and associated oncogenic pathways were attenuated in men on the glucoraphanin-rich broccoli soup in a dose-dependent manner. Although the study was not powered to assess clinical progression, an inverse association between consumption of cruciferous vegetables and cancer progression was observed. CONCLUSION: Consuming glucoraphanin-rich broccoli soup affected gene expression in the prostate of men on active surveillance, consistent with a reduction in the risk of cancer progression. This trial was registered at clinicaltrials.gov as NCT01950143.


Assuntos
Brassica/metabolismo , Glucosinolatos/metabolismo , Imidoésteres/metabolismo , Isotiocianatos/metabolismo , Próstata/metabolismo , Neoplasias da Próstata/genética , Neoplasias da Próstata/prevenção & controle , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Expressão Gênica , Humanos , Masculino , Pessoa de Meia-Idade , Oximas , Neoplasias da Próstata/metabolismo , Sulfóxidos , Transcrição Gênica , Adulto Jovem
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