Search results for "Glucuronide"
showing 10 items of 40 documents
The metabolism of mono-(2-ethylhexyl) phthalate (MEHP) and liver peroxisome proliferation in the hamster.
1988
This study has investigated the in vivo metabolism of mono-(2-ethylhexyl) phthalate (MEHP), the initial metabolite of di-(2-ethylhexyl) phthalate in mammals, and the hepatic peroxisome proliferation induced by this compound following multiple oral administration to hamsters. Hamsters received [14C]-MEHP, by gavage, at doses of 50 and 500 mg/kg body wt on each of three consecutive days. Urine was collected every 24 hours and metabolite profiles were determined using capillary gas-chromatography. Multiple high doses of MEHP (500 mg/kg) induced a change in the relative proportions of metabolites produced. As previously reported for the rat, metabolites derived from sequential ω-following by β…
Molecular docking-based design and development of a highly selective probe substrate for UDP-glucuronosyltransferase 1A10
2018
Intestinal and hepatic glucuronidation by the UDP-glucuronosyltransferases (UGTs) greatly affect the bioavailability of phenolic compounds. UGT1A10 catalyzes glucuronidation reactions in the intestine, but not in the liver. Here, our aim was to develop selective, fluorescent substrates to easily elucidate UGT1A10 function. To this end, homology models were constructed and used to design new substrates, and subsequently, six novel C3-substituted (4-fluorophenyl, 4-hydroxyphenyl, 4-methoxyphenyl, 4-(dimethylamino)phenyl, 4-methylphenyl, or triazole) 7-hydroxycoumarin derivatives were synthesized from inexpensive starting materials. All tested compounds could be glucuronidated to nonfluorescen…
Time-dependent changes in serum 3α-androstanediol glucuronide correlate with hirsutism scores after ovarian suppression
1995
The clinical utility of serum 3 alpha-androstanediol glucuronide level has been controversial. Among the concerns regarding its lack of utility has been the finding that suppression of serum 3 alpha-androstanediol glucuronide does not occur readily with treatment. We hypothesized that because the treatment of hirsutism requires a prolonged duration, a longer observation period is required for changes in serum 3 alpha-androstanediol glucuronide to be measured. Therefore, we studied the clinical and hormonal changes in 11 women treated for hirsutism with a gonadotropin-releasing hormone agonist (GnRH-a) for 1 year. A progressive reduction in Ferriman-Gallwey scores occurred, which was signifi…
The tomato sauce making process affects the bioaccessibility and bioavailability of tomato phenolics: A pharmacokinetic study
2013
Tomato sauce is the most commonly consumed processed tomato product worldwide, but very little is known about how the manufacturing process may affect the phenolic composition and bioavailability after consumption. In a prospective randomised, cross-over intervention study, we analysed the plasma and urinary levels of tomato phenolic compounds and their metabolites after acute consumption of raw tomatoes and tomato sauce, enriched or not with refined olive oil during production. Respectively, eleven and four phenolic metabolites were found in urine and plasma samples. The plasma concentration and urinary excretion of naringenin glucuronide were both significantly higher after the consumptio…
Urinary tetrahydroaldosterone as a screening method for primary aldosteronism: a comparative study
2003
Abstract Background The major aldosterone metabolite 3α,5β tetrahydroaldosterone reflects up to 45% of the aldosterone secretion. Its 24-h urinary excretion is likely to provide an accurate index of the daily aldosterone production and to be an indicator for primary aldosteronism (PA). Methods In a prospective study, the validity of tetrahydroaldosterone as a screening test for PA was evaluated in comparison to serum potassium, plasma aldosterone, plasma renin activity, plasma aldosterone/renin activity ratio (PARR), as well as 24-h urinary aldosterone-18-glucuronide and free aldosterone. A total of 111 normotensive individuals, 412 PA patients and 1453 essential hypertensive patients, were…
Alterations in androgen conjugate levels in women and men with alopecia.
1994
Objective To assess levels of androgen metabolites thought to reflect, at least in part, peripheral androgen activity in women with androgenic alopecia and men with premature balding in an effort to determine if a common abnormality exists. Design Prospective study in various groups of women and men. Setting Reproductive Endocrine Clinic at our university medical center. Patients Ten normal ovulatory female controls and 50 hyperandrogenic women divided on the basis of hirsutism and alopecia as follows: [1] 8 hirsute women with androgenic alopecia; [2] 12 nonhirsute women with androgenic alopecia; [3] 18 hirsute women without androgenic alopecia; and [4] 12 nonhirsute women without androgeni…
Evidence for increased androsterone metabolism in some normoandrogenic women with acne.
1993
Increased androgen production from the ovary, adrenal or locally in skin has been implicated in the pathogenesis of acne. Recent data have provided evidence that androsterone (Ao) metabolism is exaggerated in acne and serum metabolites of Ao differentiate between acne and hirsutism in hyperandrogenic women. Here we have extended these studies to normoandrogenic women who have moderate to severe acne. We measured serum ovarian and adrenal androgens as well as the glucuronide and sulfate metabolites of Ao and 3 alpha-androstanediol which reflect, in part, peripheral androgen action. In a group of 15 well-selected normoandrogenic patients with acne, both serum Ao glucuronide (G) and Ao were el…
An investigation of the stability of free and glucuronidated 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid in authentic urine samples.
2004
Preanalytical stability of a drug and its major metabolites is an important consideration in pharmacokinetic studies or whenever the analyte pattern is used to estimate drug habits. Firstly, the stability of free and glucuronidated 11-nor-delta9-tetrahydrocannabinol-9-carboxylic acid (THCCOOH, THCCOOglu) in authentic urine samples was investigated. Random urine samples of cannabis users (n = 38) were stored at -20, 4, and 20 degrees C up to 15 days and up to 5 days at 40 degrees C, and alterations of the analyte pattern during storage were followed by liquid chromatography-tandem mass spectrometry. Secondly, the influence of pH (range 5.0-8.0) on the stability of the analytes was studied us…
Bis(hydroxyphenyl)methane-bisphenol F-metabolism by the HepG2 human hepatoma cell line and cryopreserved human hepatocytes
2011
author cannot archive publisher's version/PDF; International audience; Bisphenol F (BPF) is present in the environment and as a contaminant of food. Humans may, therefore, be exposed to BPF, and an assessment of this risk is required. BPF has been shown to have genotoxic and endocrine-disruptor properties in a human hepatoma cell line (HepG2), which is a model system for studies of xenobiotic toxicity. In this study, we investigated the ability of HepG2 cells to biotransform BPF, because metabolism may affect the observed effects of BPF, and we compared this metabolic capacity with that of human hepatocytes. Cells were incubated for 24 hours with [(3)H]-BPF. The culture medium was then conc…
Metabolites of the aquatic pollutant diclofenac in fish bile.
2010
The uptake and metabolism of anti-inflammatory drug diclofenac (DCF) was studied by exposing rainbow trout (Oncorhynchus mykiss) to DCF intraperitoneally, and via water at concentration of 1.7 μg L(-1). The bile was collected and the formed metabolites were identified. The identification was based on the exact mass determinations by a time-of-flight mass analyzer and on the studies of fragments and fragmentation patterns of precursor ions by an ion trap mass analyzer. The main metabolites found were acyl glucuronides of hydroxylated DCFs. In addition, one ether glucuronide of hydroxylated DCF was found. Also, unmetabolized DCF was detected in the bile. The total bioconcentration factors (BC…