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1.
Nutrients ; 13(1)2020 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-33379359

RESUMO

Beer is a popular beverage and some beneficial effects have been attributed to its moderate consumption. We carried out a pilot study to test if beer and non-alcoholic beer consumption modify the levels of a panel of 53 cardiometabolic microRNAs in plasma and macrophages. Seven non-smoker men aged 30-65 with high cardiovascular risk were recruited for a non-randomised cross-over intervention consisting of the ingestion of 500 mL/day of beer or non-alcoholic beer for 14 days with a 7-day washout period between interventions. Plasma and urine isoxanthohumol were measured to assess compliance with interventions. Monocytes were isolated and differentiated into macrophages, and plasma and macrophage microRNAs were analysed by quantitative real-time PCR. Anthropometric, biochemistry and dietary parameters were also measured. We found an increase in plasma miR-155-5p, miR-328-3p, and miR-92a-3p after beer and a decrease after non-alcoholic beer consumption. Plasma miR-320a-3p levels decreased with both beers. Circulating miR-320a-3p levels correlated with LDL-cholesterol. We found that miR-17-5p, miR-20a-5p, miR-145-5p, miR-26b-5p, and miR-223-3p macrophage levels increased after beer and decreased after non-alcoholic beer consumption. Functional analyses suggested that modulated microRNAs were involved in catabolism, nutrient sensing, Toll-like receptors signalling and inflammation. We concluded that beer and non-alcoholic beer intake modulated differentially plasma and macrophage microRNAs. Specifically, microRNAs related to inflammation increased after beer consumption and decreased after non-alcoholic beer consumption.


Assuntos
Cerveja , Bebidas Gaseificadas , Fatores de Risco de Doenças Cardíacas , Macrófagos/metabolismo , MicroRNAs/metabolismo , Plasma , Adulto , Idoso , Antropometria , Escala de Avaliação Comportamental , Biomarcadores , Doenças Cardiovasculares , Estudos Cross-Over , Humanos , Inflamação , Masculino , Pessoa de Meia-Idade , Monócitos , Projetos Piloto , Fatores de Risco , Xantonas/urina
2.
BMC Pharmacol Toxicol ; 21(1): 59, 2020 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-32762728

RESUMO

BACKGROUND: Non-alcoholic fatty liver is one of the most common comorbidities of diabetes. It can cause disturbance of glucose and lipid metabolism in the body, gradually develop into liver fibrosis, and even cause liver cirrhosis. Mangiferin has a variety of pharmacological activities, especially for the improvement of glycolipid metabolism and liver injury. However, its poor oral absorption and low bioavailability limit its further clinical development and application. The modification of mangiferin derivatives is the current research hotspot to solve this problem. METHODS: The plasma pharmacokinetic of mangiferin calcium salt (MCS) and mangiferin were monitored by HPLC. The urine metabolomics of MCS were conducted by UPLC-Q-TOF-MS. RESULTS: The pharmacokinetic parameters of MCS have been varied, and the oral absorption effect of MCS was better than mangiferin. Also MCS had a good therapeutic effect on type 2 diabetes and NAFLD rats by regulating glucose and lipid metabolism. Sixteen potential biomarkers had been identified based on metabolomics which were related to the corresponding pathways including Pantothenate and CoA biosynthesis, fatty acid biosynthesis, citric acid cycle, arginine biosynthesis, tryptophan metabolism, etc. CONCLUSIONS: The present study validated the favorable pharmacokinetic profiles of MCS and the biochemical mechanisms of MCS in treating type 2 diabetes and NAFLD.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Diabetes Mellitus Tipo 2/metabolismo , Hepatopatia Gordurosa não Alcoólica/metabolismo , Xantonas/farmacocinética , Animais , Biomarcadores/metabolismo , Diabetes Mellitus Experimental/sangue , Diabetes Mellitus Experimental/urina , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/urina , Feminino , Masculino , Metabolômica , Hepatopatia Gordurosa não Alcoólica/sangue , Hepatopatia Gordurosa não Alcoólica/urina , Ratos Sprague-Dawley , Sais/sangue , Sais/farmacocinética , Sais/urina , Xantonas/sangue , Xantonas/urina
3.
Mol Nutr Food Res ; 61(10)2017 10.
Artigo em Inglês | MEDLINE | ID: mdl-28608394

RESUMO

SCOPE: The aim of this work was to study the urinary metabolomics changes of participants that consumed beer, nonalcoholic beer (na-beer), and gin. METHODS AND RESULTS: Thirty-three males at high cardiovascular risk between 55 and 75 years old participated in an open, randomized, crossover, controlled trial with three nutritional interventions consisting of beer, na-beer, and gin for 4 wk. Diet and physical activity was monitored throughout the study and compliance was assessed by measurement of urinary isoxanthohumol. Metabolomic analysis was performed in urine samples by LC coupled to an LTQ-Orbitrap mass spectrometer combined with univariate and multivariate statistical analysis. Ten metabolites were identified. Eight were exogenous metabolites related to beer, na-beer, or gin consumption, but two of them were related to endogenic changes: hydroxyadipic acid linked to fatty acid oxidation, and 4-guanidinobutanoic acid, which correlated with a decrease in urinary creatinine. Plasmatic acylcarnitines were quantified by targeted MS. A regular and moderate consumption of beer and na-beer decreased stearoylcarnitine concentrations. CONCLUSION: Humulinone and 2,3-dihydroxy-3-methylvaleric acid showed to be potential biomarkers of beer and na-beer consumption. Moreover, the results of this trial provide new evidence that the nonalcoholic fraction of beer may increase fatty oxidation.


Assuntos
Cerveja/efeitos adversos , Biomarcadores/urina , Doenças Cardiovasculares/urina , Metaboloma , Metabolômica , 3-Hidroxiacil-CoA Desidrogenases/metabolismo , Acetil-CoA C-Aciltransferase/metabolismo , Adipatos/sangue , Idoso , Consumo de Bebidas Alcoólicas , Bebidas , Isomerases de Ligação Dupla Carbono-Carbono/metabolismo , Carnitina/análogos & derivados , Carnitina/sangue , Creatinina/urina , Estudos Cross-Over , Dieta , Enoil-CoA Hidratase/metabolismo , Exercício Físico , Humanos , Masculino , Pessoa de Meia-Idade , Cooperação do Paciente , Ácidos Pentanoicos/urina , Racemases e Epimerases/metabolismo , Fatores de Risco , Xantonas/urina
4.
Mol Nutr Food Res ; 59(9): 1674-89, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26079861

RESUMO

SCOPE: Isoxanthohumol (IX) is a bioactive dietary prenylflavanone found in hops (Humulus lupulus L.), beer and nutraceuticals. IX is formed in vivo by xanthohumol and is a prodrug of 8-prenylnaringenin (8PN). IX and 8PN chirality has largely been ignored in the literature due to lack of enantiospecific bioanalytical methods. No single dose pharmacokinetic study of IX exists in the literature for any species. This study elucidates the enantiospecific pharmacokinetics of IX in rats and monitors the appearance of 8PN following intravenous and oral administration of ±IX. METHODS AND RESULTS: After intravenous (10 mg/kg) or oral (100 mg/kg) administration of ±IX to rats, serum, and urine were collected for 120 h and analyzed for IX and 8PN. Both were found as aglycones and glucuronide conjugates and displayed multiple peaking in serum suggestive of enterohepatic recycling. IX is primarily excreted through nonrenal routes. S-8PN was found excreted in the urine in greater amounts than R-8PN. Bioavailability was determined to be ∼4-5% for IX. CONCLUSION: Further enantiospecific pharmacokinetics of IX, subsequent 8PN and other metabolites are warranted along with continued enantiospecific bioactivity studies, especially in relation to gut microbial metabolism of IX and subsequent formation of 8PN.


Assuntos
Flavanonas/farmacocinética , Extratos Vegetais/farmacocinética , Xantonas/farmacocinética , Administração Intravenosa , Administração Oral , Animais , Disponibilidade Biológica , Dicroísmo Circular , Suplementos Nutricionais , Flavanonas/sangue , Flavanonas/urina , Glucuronídeos/sangue , Humulus/química , Masculino , Extratos Vegetais/sangue , Extratos Vegetais/urina , Ratos , Ratos Sprague-Dawley , Xantonas/sangue , Xantonas/urina
5.
Chin J Nat Med ; 13(2): 145-60, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25769898

RESUMO

This study aimed to profile the chemical constituents of Zi-Shen pill (ZSP) and its metabolites in plasma, urine, and prostate tissue, after administration into rats. Based on the chromatographic retention behavior, fragmentation patterns of chemical components, published literatures, and literature databases, an UPLC-Q-TOF/MS (LC-TOF/MS) method was established to identify the components of ZSP and its metabolites in biological samples. A total of 101 compounds were identified and tentatively characterized from the ZSP, including alkaloids, xanthones, and timosaponins. Except for 33 prototype components, 22 metabolites were detected in the plasma, urine, and prostate, and mainly came from Phellodendri Amurensis Cortex and Anemarrhenae Rhizoma. It was found that glucuronidation and sulfation were the major metabolic processes of xanthones, while oxidation, demethylation, and glucuronidation were the major metabolic pathways of alkaloids. In summary, the present study provided important chemical information on the metabolism of ZSP, indicating that alkaloids might be able to be absorbed into the prostate. The results provided a basis for further studies of the mechanisms of action for ZSP.


Assuntos
Medicamentos de Ervas Chinesas/metabolismo , Alcaloides/sangue , Alcaloides/urina , Animais , Cromatografia Líquida de Alta Pressão , Masculino , Plasma/química , Ratos , Espectrometria de Massas em Tandem , Urina/química , Xantonas/sangue , Xantonas/urina
6.
J Nutr ; 144(4): 484-8, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24477299

RESUMO

Biomarkers of food consumption are a powerful tool to obtain more objective measurements of dietary exposure and to monitor compliance in clinical trials. In this study, we evaluated the effectiveness of urinary isoxanthohumol (IX) excretion as an accurate biomarker of beer consumption. A dose-response clinical trial, a randomized, crossover clinical trial, and a cohort study were performed. In the dose-response trial, 41 young volunteers (males and females, aged 28 ± 3 y) consumed different doses of beer at night and a spot urine sample was collected the following morning. In the clinical trial, 33 males with high cardiovascular risk (aged 61 ± 7 y) randomly were administered 30 g of ethanol/d as gin or beer, or an equivalent amount of polyphenols as nonalcoholic beer for 4 wk. Additionally, a subsample of 46 volunteers from the PREDIMED (Prevenciόn con Dieta Mediterránea) study (males and females, aged 63 ± 5 y) was also evaluated. Prenylflavonoids were quantified in urine samples by liquid chromatography coupled to mass spectrometry. IX urinary recovery increased linearly with the size of the beer dose in male volunteers. A significant increase in IX excretion (4.0 ± 1.6 µg/g creatinine) was found after consumption of beer and nonalcoholic beer for 4 wk (P < 0.001). Receiver operating characteristic curves showed that IX is able to discriminate between beer consumers and abstainers with a sensitivity of 67% and specificity of 100% (positive predictive value = 70%, negative predictive value = 100% in real-life conditions). IX in urine samples was found to be a specific and accurate biomarker of beer consumption and may be a powerful tool in epidemiologic studies.


Assuntos
Consumo de Bebidas Alcoólicas/urina , Cerveja , Xantonas/urina , Adulto , Idoso , Bebidas Alcoólicas/efeitos adversos , Bebidas Alcoólicas/análise , Cerveja/efeitos adversos , Cerveja/análise , Bebidas/análise , Consumo Excessivo de Bebidas Alcoólicas/diagnóstico , Consumo Excessivo de Bebidas Alcoólicas/urina , Biomarcadores/urina , Estudos de Coortes , Estudos Cross-Over , Dieta , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Espanha , Detecção do Abuso de Substâncias
7.
Anal Chem ; 85(11): 5547-54, 2013 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-23642016

RESUMO

The interest in studying hops and beer prenylflavanoids, isoxanthohumol, xanthohumol, and 8-prenylnaringenin, has increased in recent years due to their biological activity as strong phytoestrogens and potent cancer chemopreventive agents. However, prenylflavanoids behave differently from most polyphenols, since they are unstable at acidic pH. To our knowledge, no published studies to date have considered the degradation of these compounds during analytical processes. In the present work, a new sensitive and specific method based on solid phase extraction and liquid chromatography coupled to electrospray ionization triple quadruple mass spectrometry (LC-ESI-MS/MS) was developed and validated. The new method was optimized to avoid degradation of the selected analytes, isoxanthohumol, xanthohumol, and 8-prenylnaringenin, throughout the analytical process and to reduce the urine matrix effect in LC-ESI-MS/MS assays. It was concluded that a neutral pH (pH 7.0) is necessary for the analysis of prenylflavanoids, in order to maintain the stability of compounds for at least 24 h. The addition of ascorbic acid to the media improved stability, calibration curves, coefficients of correlation, accuracy, and precision parameters. Mix-mode cation exchange sorbent yielded the best matrix effect factors and recoveries. Method validation results showed appropriate intraday and interday accuracy and precision (<15%). Recovery of isoxanthohumol, xanthohumol, and 8-prenylnaringenin was 97.1% ± 0.03, 105.8% ± 0.05, and 105.4% ± 0.04, respectively, and matrix effect factors were nearly 100%. The stability assay showed that analytes were stable for at least 24 h. The method was applied to quantify 10 human samples of urine and was able to quantify prenylflavanoids in urine after the consumption of a single dose of beer (330 mL).


Assuntos
Cromatografia Líquida/métodos , Flavanonas/urina , Flavonoides/urina , Polifenóis/análise , Propiofenonas/urina , Espectrometria de Massas por Ionização por Electrospray/métodos , Espectrometria de Massas em Tandem/métodos , Xantonas/urina , Ácidos/química , Adulto , Humanos , Masculino , Extração em Fase Sólida , Adulto Jovem
8.
Drug Metab Dispos ; 40(11): 2109-18, 2012 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-22859782

RESUMO

To clarify the role of the intestinal flora in the absorption and metabolism of mangiferin and to elucidate its metabolic fate and pharmacokinetic profile in diabetic rats, a systematic and comparative investigation of the metabolism and pharmacokinetics of mangiferin in conventional rats, pseudo-germ-free rats, and streptozotocin (STZ)-induced diabetic rats was conducted. Forty-eight metabolites of mangiferin were detected and identified in the urine, plasma, and feces after oral administration (400 mg/kg). Mangiferin underwent extensive metabolism in conventional rats and diabetic rats, but the diabetic rats exhibited a greater number of metabolites compared with that of conventional rats. When the intestinal flora were inhibited, deglycosylation of mangiferin and sequential biotransformations would not occur. Pharmacokinetic studies indicated a 2.79- and 2.35-fold increase in the plasma maximum concentration and the area under the concentration-time curve from 0 to 24 h of mangiferin in diabetic rats compared with those for conventional rats, whereas no significant differences were observed between conventional rats and pseudo-germ-free rats. Further real-time quantitative reverse transcription-polymerase chain reaction results indicated that the multidrug resistance (mdr) 1a level in the ileum increased, whereas its level in the duodenum and the mdr1b mRNA levels in the duodenum, jejunum, and ileum decreased in diabetic rats compared with those in conventional rats. With regard to the pseudo-germ-free rats, up-regulated mdr1a mRNA levels and down-regulated mdr1b mRNA levels in the small intestines were observed. The diabetic status induced increased UDP-glucuronosyltransferase (UGT) 1A3, UGT1A8, UGT2B8, and sulfotransferase (SULT) 1A1 mRNA levels and decreased catechol-O-methyltransferase (COMT), UGT2B6, UGT2B12, and SULT1C1 mRNA levels. These results might partially explain the different pharmacokinetic and metabolic disposition of mangiferin among conventional and model rats.


Assuntos
Diabetes Mellitus Experimental/metabolismo , Intestino Delgado/metabolismo , Xantonas/farmacocinética , Subfamília B de Transportador de Cassetes de Ligação de ATP/genética , Subfamília B de Transportador de Cassetes de Ligação de ATP/metabolismo , Animais , Arilsulfotransferase/genética , Arilsulfotransferase/metabolismo , Catecol O-Metiltransferase/genética , Catecol O-Metiltransferase/metabolismo , Regulação para Baixo , Fezes/química , Vida Livre de Germes , Glucuronosiltransferase/genética , Glucuronosiltransferase/metabolismo , Absorção Intestinal , Masculino , Desintoxicação Metabólica Fase II , RNA Mensageiro/genética , Ratos , Ratos Wistar , Regulação para Cima , Xantonas/sangue , Xantonas/urina , Membro 4 da Subfamília B de Transportadores de Cassetes de Ligação de ATP
9.
J Nutr ; 142(4): 675-80, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22399525

RESUMO

The proposed health-promoting effects of the pericarp from mangosteen fruit have been attributed to a family of polyphenols referred to as xanthones. The purpose of this study was to determine the bioavailability of xanthones from 100% mangosteen juice in healthy adult participants (n = 10). Pericarp particles accounted for 1% of the mass and 99% of the xanthone concentration in the juice. The juice provided 5.3 ± 0.1 mmol/L total xanthones with α-mangostin, garcinones (C, D, and E), γ-mangostin, gartanins, and other identified xanthones accounting for 58, 2, 6, 4, and 5%, respectively. Participants ingested 60 mL mangosteen juice with a high-fat breakfast. Free and conjugated (glucuronidated/sulfated) xanthones were detected in serum and urine. There was marked variation in the AUC (762-4030 nmol/L × h), maximum concentration (113 ± 107 nmol/L), and time to maximum concentration (3.7 ± 2.4 h) for α-mangostin in sera during the 24-h collection. Similarly, xanthones in 24-h urine ranged from 0.9 to 11.1 µmol and accounted for 2.0 ± 0.3% (range 0.3-3.4%) of the ingested dose. There were no significant differences between female and male participants in mean pharmacokinetic values of α-mangostin in serum and urinary xanthones. Only 15.4 ± 0.7% of total xanthones in pericarp particles in the juice partitioned into mixed micelles during in vitro digestion. These results show that xanthones in mangosteen juice are absorbed when ingested along with a high-fat meal, although release of xanthones from pericarp particles during digestion may be limited.


Assuntos
Bebidas/análise , Frutas/química , Garcinia mangostana/química , Absorção Intestinal , Xantonas/metabolismo , Adulto , Cromatografia Líquida de Alta Pressão , Digestão , Feminino , Glucuronídeos/sangue , Glucuronídeos/metabolismo , Glucuronídeos/urina , Humanos , Cinética , Limite de Detecção , Masculino , Micelas , Ohio , Espectrometria de Massas por Ionização por Electrospray , Sulfatos/sangue , Sulfatos/metabolismo , Sulfatos/urina , Xantonas/análise , Xantonas/sangue , Xantonas/urina
10.
Mol Nutr Food Res ; 54(10): 1405-13, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20397197

RESUMO

The impact of human intestinal bacteria on the bioavailability of the prenylflavonoid xanthohumol (XN) was studied by comparing germ-free (GF) and human microbiota-associated (HMA) rats. After XN application, XN, XN conjugates, and isoxanthohumol (IX) conjugates occurred in blood samples of GF and HMA rats, whereas IX was detected only in the blood of HMA rats. Overall excretion of XN and its metabolites within 48 h was only 4.6% of the ingested dose in GF rats and 4.2% in HMA rats, feces being the major route of excretion. While both GF and HMA rats excreted XN, IX, and their conjugates with urine and feces, 8-prenylnaringenin and its corresponding conjugates were exclusively observed in the feces of HMA rats. The microbial formation of 8-prenylnaringenin was confirmed by incubation of XN and IX with human fecal slurries. The amount of conjugates excreted in urine and feces was lower in HMA rats compared to GF rats indicating their hydrolysis by human intestinal microbiota. Thus, the impact of bacteria on the XN metabolism in the gut may affect the in vivo effects of ingested XN.


Assuntos
Antioxidantes/metabolismo , Antioxidantes/farmacocinética , Flavonoides/metabolismo , Flavonoides/farmacocinética , Mucosa Intestinal/metabolismo , Intestinos/microbiologia , Metagenoma/fisiologia , Propiofenonas/metabolismo , Propiofenonas/farmacocinética , Animais , Antioxidantes/química , Disponibilidade Biológica , Biotransformação , Fezes/química , Fezes/microbiologia , Feminino , Flavanonas/análise , Flavanonas/metabolismo , Flavonoides/química , Suco Gástrico/química , Suco Gástrico/metabolismo , Conteúdo Gastrointestinal/química , Conteúdo Gastrointestinal/microbiologia , Vida Livre de Germes , Humanos , Masculino , Desintoxicação Metabólica Fase II , Pessoa de Meia-Idade , Propiofenonas/química , Ratos , Ratos Sprague-Dawley , Xantonas/análise , Xantonas/sangue , Xantonas/metabolismo , Xantonas/urina
11.
Biomed Chromatogr ; 22(10): 1066-83, 2008 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-18506725

RESUMO

Rhizoma Anemarrhenae (Zhimu in Chinese), the dried rhizome of Anemarrhena asphodeloides Bge. (Fam. Liliaceae), is a well-known traditional Chinese medicinal herb and has been used clinically in China for centuries to cure various diseases. However, like other traditional Chinese medicines, the effective constituents of this medicine, especially the assimilation and metabolites in vivo, which are very important to show their effects, have not been systematically studied. In this paper, solid-phase extraction and liquid chromatography-atmospheric pressure chemical ionization mass spectrometry technologies were used to study the constituents absorbed into rat urine and their metabolites after oral administration of Rhizoma Anemarrhenae decoction. A total of 11 compounds, including two xanthones, three of their metabolites and six steroidal saponins, were identified in rat urine sample. They were neomangiferin (1), glucuronide and monomethyl conjugate of mangiferin (2), mangiferin (3), monomethyl conjugate of mangiferin (4), dimethyl conjugate of mangiferin (5), timosaponin N or timosaponin E1 (6), timosaponin BII (7), timosaponin BIII (8), anemarrhenasaponin I or anemarrhenasaponin II (9), timosaponin AII (10) and timosaponin AIII (11). The results would efficaciously narrow the potentially active compounds range in Rhizoma Anemarrhenae decoction, and pave a helpful way for follow-up mechanism of action research.


Assuntos
Anemarrhena/química , Cromatografia Líquida de Alta Pressão/métodos , Saponinas/urina , Espectrometria de Massas em Tandem/métodos , Xantonas/urina , Administração Oral , Animais , Masculino , Extratos Vegetais/administração & dosagem , Extratos Vegetais/análise , Ratos , Rizoma/química
12.
J Pharm Biomed Anal ; 45(5): 793-8, 2007 Dec 21.
Artigo em Inglês | MEDLINE | ID: mdl-17723287

RESUMO

Four metabolites of mangiferin were firstly isolated and identified from rat urine. The structures of the four metabolites were determined to be 1,3,7-trihydroxyxanthone (M-1), 1,3,6,7-tetrahydroxyxanthone (M-2), 1,3,6-trihydroxy-7-methoxyxanthone (M-3) and 1,7-dihydroxyxanthone (M-4), respectively. A simple and specific analytical method for determination of the four metabolites in rat urine was developed by high performance liquid chromatography (HPLC). Quercetin was employed as an internal standard. The correlation coefficients of the calibration curves were higher than 0.997, both intra- and inter-day precision of four metabolites were determined and their R.S.D. did not exceed 10%. The accuracy and linear range had been investigated in detail. The cumulative urinary excretions of the four metabolites were measured and the possible metabolic pathway of the metabolites was discussed.


Assuntos
Xantonas/isolamento & purificação , Xantonas/urina , Administração Oral , Anemarrhena/anatomia & histologia , Animais , Calibragem , Cromatografia Líquida de Alta Pressão/métodos , Estabilidade de Medicamentos , Masculino , Medicina Tradicional Chinesa , Estrutura Molecular , Raízes de Plantas/química , Quercetina/química , Ratos , Ratos Sprague-Dawley , Padrões de Referência , Reprodutibilidade dos Testes , Temperatura , Fatores de Tempo , Xantonas/administração & dosagem , Xantonas/química , Xantonas/metabolismo
13.
Br J Nutr ; 98(5): 950-9, 2007 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-17521469

RESUMO

Hop-derived food supplements and beers contain the prenylflavonoids xanthohumol (X), isoxanthohumol (IX) and the very potent phyto-oestrogen (plant-derived oestrogen mimic) 8-prenylnaringenin (8-PN). The weakly oestrogenic IX can be bioactivated via O-demethylation to 8-PN. Since IX usually predominates over 8-PN, human subjects may be exposed to increased doses of 8-PN. A dietary intervention trial with fifty healthy post-menopausal Caucasian women was undertaken. After a 4 d washout period, participants delivered faeces, blank urine and breath samples. Next, they started a 5 d treatment with hop-based supplements that were administered three times per d and on the last day, a 24 h urine sample was collected. A semi-quantitative FFQ was used to estimate fat, fibre, alcohol, caffeine and theobromine intakes. The recoveries of IX, 8-PN and X in the urine were low and considerable inter-individual variations were observed. A five-fold increase in the dosage of IX without change in 8-PN concentration resulted in a significant lower IX recovery and a higher 8-PN recovery. Classification of the subjects into poor (60%), moderate (25%) and strong (15%) 8-PN producers based on either urinary excretion or microbial bioactivation capacity gave comparable results. Recent antibiotic therapy seemed to affect the 8-PN production negatively. A positive trend between methane excretion and 8-PN production was observed. Strong 8-PN producers consumed less alcohol and had a higher theobromine intake. From this study we conclude that in vivo O-demethylation of IX increases the oestrogenic potency of hop-derived products.


Assuntos
Suplementos Nutricionais , Flavanonas/biossíntese , Humulus , Pós-Menopausa/fisiologia , Idoso , Antibacterianos/farmacologia , Dieta , Fezes/química , Fezes/microbiologia , Feminino , Flavanonas/urina , Flavonoides , Trato Gastrointestinal/microbiologia , Humanos , Metano/biossíntese , Pessoa de Meia-Idade , Fenótipo , Fitoestrógenos/metabolismo , Propiofenonas/urina , Xantonas/urina
14.
Biomed Chromatogr ; 20(12): 1304-8, 2006 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-17006966

RESUMO

A reversed-phase high-performance liquid chromatography assay for mangiferin in rat plasma and urine was developed. Rutin was employed as an internal standard. The mobile phase consisted of acetonitrile-water (16:84, v/v) containing 3% acetic acid at a flow rate of 1 mL/min. Detection was at 257 and 365 nm for mangiferin in plasma and urine, respectively. The limit of quantitation (LOQ) of mangiferin was 0.6 microg/mL in plasma, and 0.48 microg/mL in urine. The standard curve was linear from 0.6 to 24 microg/mL in plasma, and 0.48 to 24 microg/mL in urine, both intra- and inter-day precision of the mangiferin were determined and their RSD did not exceed 10%. The method provides a technique for rapid analysis of mangiferin in rat plasma and urine, which can be used in pharmacokinetic studies.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Xantonas/sangue , Xantonas/urina , Administração Oral , Animais , Masculino , Ratos , Ratos Sprague-Dawley , Reprodutibilidade dos Testes , Xantonas/administração & dosagem , Xantonas/farmacocinética
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