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1.
Phytochem Anal ; 29(6): 613-626, 2018 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-29968391

RESUMEN

INTRODUCTION: Pro-toxic dehydropyrrolizidine alkaloids are associated with liver disease in humans. The potential for long-term, low-level or intermittent exposures to cause or contribute to chronically-developing diseases is of international concern. Eupatorium perfoliatum is a medicinal herb referred to as boneset. While the presence of dehydropyrrolizidine alkaloids in some Eupatorium species is well-established, reports on Eupatorium perfoliatum are scant and contradictory. OBJECTIVE: To investigate the presence of dehydropyrrolizidine alkaloids in a survey of boneset samples and related alcoholic tinctures, and hot water infusions and decoctions. METHODS: Methanol, hot water or aqueous ethanol extracts of Eupatorium perfoliatum and three closely-related species were subjected to HPLC-ESI(+)MS and MS/MS analysis using three complementary column methods. Dehydropyrrolizidine alkaloids were identified from their MS data and comparison with standards. RESULTS: Forty-nine samples of Eupatorium perfoliatum were shown to contain dehydropyrrolizidine alkaloids (0.0002-0.07% w/w), the majority dominated by lycopsamine and intermedine, their N-oxides and acetylated derivatives. Alcoholic tinctures and hot water infusions and decoctions had high concentrations of the alkaloids. Different chemotypes, hybridisation or contamination of some Eupatorium perfoliatum samples with related species were suggested by the co-presence of retronecine- and heliotridine-based alkaloids. CONCLUSIONS: Sampling issues, low and high alkaloid chemotypes of Eupatorium perfoliatum or interspecies hybridization could cause the wide variation in dehydropyrrolizidine alkaloid concentrations or the different profiles observed. Concerns associated with dehydropyrrolizidine alkaloids provide a compelling reason for preclusive caution until further research can better define the toxicity and carcinogenicity of the dehydropyrrolizidine alkaloid content of Eupatorium perfoliatum. [Correction added on 12 July 2018, after first online publication: The 'Conclusions' section in the abstract has been added.].


Asunto(s)
Eupatorium/química , Alcaloides de Pirrolicidina/toxicidad , Eupatorium/genética , Eupatorium/metabolismo , Hibridación Genética , Estructura Molecular , Extractos Vegetales/química , Extractos Vegetales/toxicidad , Alcaloides de Pirrolicidina/química , Especificidad de la Especie , Espectrometría de Masas en Tándem
2.
Anal Bioanal Chem ; 405(13): 4531-8, 2013 May.
Artículo en Inglés | MEDLINE | ID: mdl-23371533

RESUMEN

As part of a collaboration with the National Institutes of Health's Office of Dietary Supplements and the Food and Drug Administration's Center for Drug Evaluation and Research, the National Institute of Standards and Technology has developed Standard Reference Material (SRM) 3274 Botanical Oils Containing Omega-3 and Omega-6 Fatty Acids and SRM 3275 Omega-3 and Omega-6 Fatty Acids in Fish Oil. SRM 3274 consists of one ampoule of each of four seed oils (3274-1 Borage (Borago officinalis), 3274-2 Evening Primrose (Oenothera biennis), 3274-3 Flax (Linium usitatissimum), and 3274-4 Perilla (Perilla frutescens)), and SRM 3275 consists of two ampoules of each of three fish oils (3275-1 a concentrate high in docosahexaenoic acid, 3275-2 an anchovy oil high in docosahexaenoic acid and eicosapentaenoic acid, and 3275-3 a concentrate containing 60% long-chain omega-3 fatty acids). Each oil has certified and reference mass fraction values for up to 20 fatty acids. The fatty acid mass fraction values are based on results from analyses using gas chromatography with flame ionization detection (GC-FID) and mass spectrometry (GC/MS). These SRMs will complement other reference materials currently available with mass fractions for similar analytes and are part of a series of SRMs being developed for dietary supplements.


Asunto(s)
Suplementos Dietéticos/normas , Ácidos Docosahexaenoicos/normas , Ácido Eicosapentaenoico/normas , Aceites de Pescado/normas , Aceites de Plantas/normas , Cromatografía de Gases , Suplementos Dietéticos/análisis , Ácidos Docosahexaenoicos/aislamiento & purificación , Ácido Eicosapentaenoico/aislamiento & purificación , Aceites de Pescado/química , Ionización de Llama , Humanos , Aceites de Plantas/química , Estándares de Referencia , Valores de Referencia
3.
JAMA ; 306(12): 1344-51, 2011 Sep 28.
Artículo en Inglés | MEDLINE | ID: mdl-21954478

RESUMEN

CONTEXT: Saw palmetto fruit extracts are widely used for treating lower urinary tract symptoms attributed to benign prostatic hyperplasia (BPH); however, recent clinical trials have questioned their efficacy, at least at standard doses (320 mg/d). OBJECTIVE: To determine the effect of saw palmetto extract (Serenoa repens, from saw palmetto berries) at up to 3 times the standard dose on lower urinary tract symptoms attributed to BPH. DESIGN, SETTING, AND PARTICIPANTS: A double-blind, multicenter, placebo-controlled randomized trial at 11 North American clinical sites conducted between June 5, 2008, and October 10, 2010, of 369 men aged 45 years or older, with a peak urinary flow rate of at least 4 mL/s, an American Urological Association Symptom Index (AUASI) score of between 8 and 24 at 2 screening visits, and no exclusions. INTERVENTIONS: One, 2, and then 3 doses (320 mg/d) of saw palmetto extract or placebo, with dose increases at 24 and 48 weeks. MAIN OUTCOME MEASURES: Difference in AUASI score between baseline and 72 weeks. Secondary outcomes included measures of urinary bother, nocturia, peak uroflow, postvoid residual volume, prostate-specific antigen level, participants' global assessments, and indices of sexual function, continence, sleep quality, and prostatitis symptoms. RESULTS: Between baseline and 72 weeks, mean AUASI scores decreased from 14.42 to 12.22 points (-2.20 points; 95% CI, -3.04 to -1.36) [corrected]with saw palmetto extract and from 14.69 to 11.70 points (-2.99 points; 95% CI, -3.81 to -2.17) with placebo. The group mean difference in AUASI score change from baseline to 72 weeks between the saw palmetto extract and placebo groups was 0.79 points favoring placebo (upper bound of the 1-sided 95% CI most favorable to saw palmetto extract was 1.77 points, 1-sided P = .91). Saw palmetto extract was no more effective than placebo for any secondary outcome. No clearly attributable adverse effects were identified. CONCLUSION: Increasing doses of a saw palmetto fruit extract did not reduce lower urinary tract symptoms more than placebo. TRIAL REGISTRATION: clinicaltrials.gov Identifier: NCT00603304.


Asunto(s)
Antagonistas de Andrógenos/administración & dosificación , Extractos Vegetales/administración & dosificación , Hiperplasia Prostática/complicaciones , Trastornos Urinarios/tratamiento farmacológico , Anciano , Relación Dosis-Respuesta a Droga , Método Doble Ciego , Humanos , Masculino , Persona de Mediana Edad , Serenoa , Resultado del Tratamiento , Trastornos Urinarios/etiología
4.
Am J Clin Nutr ; 92(2): 383-9, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20573790

RESUMEN

BACKGROUND: Unmetabolized serum folic acid (UMFA) has been detected in adults. Previous research indicates that high folic acid intakes may be associated with risk of cancer. OBJECTIVE: The objective was to examine UMFA concentrations in relation to dietary and supplemental folate and status biomarkers in the US population aged > or =60 y. DESIGN: Surplus sera were analyzed with the use of data from the National Health and Nutrition Examination Survey (NHANES) 2001-2002, a cross-sectional, nationally representative survey (n = 1121). RESULTS: UMFA was detected in 38% of the population, with a mean concentration of 4.4 +/- 0.6 nmol/L (median: 1.2+/- 0.2 nmol/L). The group with UMFA (UMFA+) had a significantly higher proportion of folic acid supplement users than did the group without UMFA (60% compared with 41%). UMFA+ men and women also had higher supplemental and total (food + supplements) folic acid intakes than did their counterparts without UMFA. Forty percent of the UMFA+ group was in the highest quartile of total folic acid intake, but total folic acid intake was only moderately related to UMFA concentrations (r(2) = 0.07). Serum folate concentrations were significantly higher in the UMFA+ group and were predictive of UMFA concentrations (r(2) = 0.15). Serum 5-methyltetrahydrofolate and vitamin B-12 concentrations were higher in the UMFA+ group, whereas there was no difference between the 2 UMFA groups in red blood cell folate, serum homocysteine, or methylmalonic acid concentrations. CONCLUSIONS: Approximately 40% of older adults in the United States have UMFA that persists after a fast, and the presence of UMFA is not easily explained in NHANES by folic acid intakes alone. Given the possibility that excessive folic acid exposure may relate to cancer risk, monitoring of UMFA may be warranted.


Asunto(s)
Dieta , Suplementos Dietéticos , Ácido Fólico/sangre , Anciano , Eritrocitos/química , Femenino , Ácido Fólico/administración & dosificación , Ácido Fólico/metabolismo , Homocisteína/sangre , Humanos , Masculino , Ácido Metilmalónico/sangre , Encuestas Nutricionales , Tetrahidrofolatos/sangre , Estados Unidos , Vitamina B 12/sangre
5.
Food Chem Toxicol ; 46(1): 168-74, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-17822821

RESUMEN

Kava (Piper methysticum) is a member of the pepper family and has been cultivated by South Pacific islanders for centuries and used as a social and ceremonial drink. Traditionally, kava extracts are prepared by grinding or chewing the rhizome and mixing with water and coconut milk. The active constituents of kava are a group of approximately 18 compounds collectively referred to as kavalactones or kava pyrones. Kawain, dihydrokawain, methysticin, dihydromethysticin, yangonin, and desmethoxyyangonin are the six major kavalactones. Kava beverages and other preparations are known to be anxiolytic and are used for anxiety disorders. Dietary supplements containing the root of the kava shrub have been implicated in several cases of liver toxicity in humans, including several who required liver transplants after using kava supplements. In order to study the toxicity and mutagenicity, two commercial samples of kava, Kaviar and KavaPure, and the six pure kavalactones including both D-kawain and DL-kawain, were evaluated in L5178Y mouse lymphoma cells. Neither the kava samples nor the kavalactones induced a mutagenic response in the L5178Y mouse lymphoma mutation assay with the addition of human liver S9 activation.


Asunto(s)
Citotoxinas/toxicidad , Kava/toxicidad , Lactonas/toxicidad , Mutágenos , Animales , Línea Celular Tumoral , Cromatografía Líquida de Alta Presión , Citotoxinas/química , Humanos , Kava/química , Lactonas/química , Hígado/metabolismo , Hígado/ultraestructura , Linfoma/genética , Espectrometría de Masas , Ratones , Pruebas de Mutagenicidad , Mutación/efectos de los fármacos , Mutación/genética , Extractos Vegetales/toxicidad , Fracciones Subcelulares/metabolismo , Fracciones Subcelulares/ultraestructura
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