Urinary pharmacokinetics of the glucuronide and sulfate conjugates of genistein and daidzein.
نویسندگان
چکیده
Consumption of soybean-rich diets is thought to provide significant health benefits such as prevention of cancer, primarily because of the high contents of factors such as the isoflavones genistein and daidzein. Isoflavones circulate and are excreted into the urine mainly as glucuronide and sulfate conjugates. This study was conducted to determine the urinary pharmacokinetics of sulfate and glucuronide conjugates of genistein and daidzein. Twelve volunteers consumed a soy beverage providing 1 and 0.6 mg/kg body weight of genistein and daidzein equivalents, respectively. Urine was collected at various times during the 48 h after soy consumption and was digested with either glucuronidase or sulfatase, and the liberated aglycones were extracted and analyzed by liquid chromatography-mass spectrometry. Urinary isoflavone sulfate levels were determined by two methods: (a) assessment of aglycone after sulfatase hydrolysis (measured); or (b) calculated by subtracting the aglycone + glucuronide levels from the total urinary isoflavone levels. The apparent terminal half-life for daidzein sulfate (3.9+/-0.5 h) that was determined from sulfatase-treated urine was 32% shorter (P < or = 0.02) than that of the calculated daidzein sulfate (5.7+/-0.08 h). A similar trend was obtained for genistein sulfate (4.5+/-0.7 versus 6.8+/-0.1 h). The apparent terminal half-lives for genistein and daidzein glucuronides were 6.0+/-0.4 and 3.8+/-0.4 h, respectively. These data suggest that the measured urinary isoflavone sulfate values provide a better understanding of the pharmacokinetics than the calculated values. Additional studies are needed to determine whether the apparent terminal half-lives can be attributed to elimination or absorption processes.
منابع مشابه
Pharmacokinetics of the glucuronide and sulfate conjugates of genistein and daidzein in men and women after consumption of a soy beverage.
BACKGROUND The soy isoflavones genistein and daidzein are found in blood and tissues as aglycones, glucuronides, and sulfates. Isoflavone conjugates may serve as sources of aglycones at specific target tissues and may have bioactivity. Yet, very little is known about the plasma pharmacokinetics of isoflavone conjugates after soy ingestion. OBJECTIVE The objective of this study was to determin...
متن کاملMetabolism and disposition of isoflavone conjugated metabolites in humans after ingestion of kinako.
Isoflavone aglycones daidzein (Dein) and genistein (Gein) are present primarily as glucuronides and sulfates in human plasma; however, very little is known about the plasma pharmacokinetics of isoflavone conjugates after soy ingestion. The aim of this study was to investigate metabolism and disposition of the isoflavone conjugated metabolites glucuronide or sulfate or both after ingestion of ki...
متن کاملPlasma profiling of intact isoflavone metabolites by high-performance liquid chromatography and mass spectrometric identification of flavone glycosides daidzin and genistin in human plasma after administration of kinako.
The roles of isoflavones in the prevention of several hormone-dependent cancers and osteoporosis are of great interest. Despite many pharmacokinetics studies of the isoflavones, the actual types of conjugates circulating in the body and the position(s) of conjugation sites on the flavone skeleton are still uncertain because, in general, conjugated compounds in biological fluids have been evalua...
متن کاملBioavailability of the glucuronide and sulfate conjugates of genistein and daidzein in Bcrp1 knockout mice
متن کامل
Effects of Vitamin D Plus Calcium Supplements on Pharmacokinetics of Isoflavones in Thai Postmenopausal Women
The objective of this study was to determine the effects of vitamin D(3) plus calcium supplements (D(3)-calcium) on pharmacokinetics of isoflavones in Thai postmenopausal women. This study was an open-labeled, randomized three-phase crossover study. Twelve healthy subjects were randomized to receive one of the following regimens: (a) a single dose of isoflavones, (b) a single dose of isoflavone...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- Cancer epidemiology, biomarkers & prevention : a publication of the American Association for Cancer Research, cosponsored by the American Society of Preventive Oncology
دوره 9 4 شماره
صفحات -
تاریخ انتشار 2000