Effect of switching to risperidone after unsuccessful treatment with aripiprazole on plasma monoamine metabolites level in the treatment of acute schizophrenia.

Science.gov (United States)

Miura, Itaru; Takeuchi, Satoshi; Katsumi, Akihiko; Kanno, Keiko; Watanabe, Kenya; Mashiko, Hirobumi; Niwa, Shin-Ichi

2012-09-01

In the treatment of acute schizophrenia, risperidone and aripiprazole are both placed the first line antipsychotics. These two antipsychotics have different pharmacological effects. We investigated the effects of risperidone on plasma levels of homovanillic acid (HVA) and 3-methoxy-4hydroxyphenylglycol after unsuccessful aripiprazole treatment in acute schizophrenia. Ten Japanese patients with acute schizophrenia were enrolled to this study. Plasma levels of monoamine metabolites were analyzed with high-performance liquid chromatography with electrochemical detection. Risperidone improved the symptoms and 4 of 10 patients were responders. Risperidone showed a tendency to decrease plasma HVA (pHVA) levels in responders (p = 0.068), but not in non-responders (p = 1.0). At baseline, pHVA levels of responders were significantly higher than that of non-responders (p = 0.033). A trend for negative correlation was found between pHVA at baseline and the changes in Positive and Negative Syndrome Scale-Total (p = 0.061, r = -0.61). Our results suggest that high pHVA level before switching may predict good response to the second line antipsychotics after unsuccessful first antipsychotic treatment. If aripiprazole is not effective in acute schizophrenia, switching to risperidone may be effective and reasonable strategy for improving symptoms. Copyright © 2012 John Wiley & Sons, Ltd.

PCB 28 metabolites elimination kinetics in human plasma on a real case scenario: Study of hydroxylated polychlorinated biphenyl (OH-PCB) metabolites of PCB 28 in a highly exposed German Cohort.

Science.gov (United States)

Quinete, Natalia; Esser, André; Kraus, Thomas; Schettgen, Thomas

2017-07-05

Polychlorinated biphenyls (PCBs) are suspected of carcinogenic, neurotoxic and immunotoxic effects in animals and humans. Although background levels of PCBs have been slowly decreased after their ban, they are still among the most persistent and ubiquitous pollutants in the environment, remaining the subject of great concern. PCB 28 is a trichlorinated PCB found in high concentrations not only in human plasma but also in indoor air in Europe, yet little is known about its metabolic pathway and potential metabolites in humans. The present study aims to elucidate the kinetics of metabolite formation and elimination by analyzing four hydroxylated PCBs (OH-PCBs) in human plasma as potential metabolites of the PCB 28 congener. For this purpose, the study was conducted in plasma samples of highly PCB-exposed individuals (N=268), collected from 2010 to 2014 as a representation of a real case scenario with longitudinal data. OH-PCBs have been predicted, synthesized in the course of this study and further identified and quantitated in human plasma. This is the first time that previously unknown PCB 28 metabolites have been measured in human plasma and half-lives have been estimated for PCB metabolites, which could then provide further understanding in the toxicological consequences of exposure to PCBs in humans. Copyright © 2017 Elsevier B.V. All rights reserved.

Eicosanoid and cytokine levels in plasma of patients during mesenteric infarction

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N. Nathan

1997-01-01

Full Text Available Multible organ failure (MOF induced by mesenteric infarction is associated with a high mortality rate. This study reports eicosanoid and cytokine levels in the blood of three atherosclerotic patients who ultimately died from MOF induced by mesenteric infarction. High plasma levels of 6- keto-prostaglandin (PG F1α (the stable metabolite of PGI2, interleukin (IL-6 and IL-8 are observed whereas plasma tumour necrosis factor alpha (TNFα, TxB2 (the stable metabolite of TxA2, PGE2, leukotrienes (LTB4 and LTC4, and whole blood platelet-activating factor levels are not different from values obtained in similarly severe atherosclerotic patients. This short report questioned the clinical involvement of TNFα during such a pathology where a persistent translocation of endotoxin has been observed through the gut endothelial barrier. Activation of phospholipase A2 is suggested by the increase in the stable metabolite of PGI2 and might be by itself or through lipidic metabolites, a major systemic stimulus of IL-6 and IL-8 production.

Hepatitis C virus infection influences the S-methadone metabolite plasma concentration.

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Shiow-Ling Wu

Full Text Available Heroin-dependent patients typically contract hepatitis C virus (HCV at a disproportionately high level due to needle exchange. The liver is the primary target organ of HCV infection and also the main organ responsible for drug metabolism. Methadone maintenance treatment (MMT is a major treatment regimen for opioid dependence. HCV infection may affect methadone metabolism but this has rarely been studied. In our current study, we aimed to test the hypothesis that HCV may influence the methadone dosage and its plasma metabolite concentrations in a MMT cohort from Taiwan.A total of 366 MMT patients were recruited. The levels of plasma hepatitis B virus (HBV, HCV, human immunodeficiency virus (HIV antibodies (Ab, liver aspartate aminotransferase (AST and alanine aminotransferase (ALT, as well as methadone and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP were measured along with the urine morphine concentration and amphetamine screening.Of the 352 subjects in our cohort with HCV test records, 95% were found to be positive for plasma anti-HCV antibody. The liver functional parameters of AST (Wilcoxon Rank-Sum test, P = 0.02 and ALT (Wilcoxon Rank-Sum test, P = 0.04, the plasma methadone concentrations (Wilcoxon Rank-Sum test, P = 0.043 and the R-enantiomer of methadone concentrations (Wilcoxon Rank-Sum test, P = 0.032 were significantly higher in the HCV antibody-positive subjects than in the HCV antibody-negative patients, but not the S-EDDP/methadone dose ratio. The HCV levels correlated with the methadone dose (β= 14.65 and 14.13; P = 0.029 and 0.03 and the S-EDDP/methadone dose ratio (β= -0.41 and -0.40; P = 0.00084 and 0.002 in both univariate and multivariate regression analyses.We conclude that HCV may influence the methadone dose and plasma S-EDDP/methadone dose ratio in MMT patients in this preliminary study.

GMP-compliant radiosynthesis of [18F]altanserin and human plasma metabolite studies

International Nuclear Information System (INIS)

Hasler, F.; Kuznetsova, O.F.; Krasikova, R.N.; Cservenyak, T.; Quednow, B.B.; Vollenweider, F.X.; Ametamey, S.M.; Westera, G.

2009-01-01

[ 18 F]altanserin is the preferred radiotracer for in-vivo labeling of serotonin 2A receptors by positron emission tomography (PET). We report a modified synthesis procedure suited for reliable production of multi-GBq amounts of [ 18 F]altanserin useful for application in humans. We introduced thermal heating for drying of [ 18 F]fluoride as well as for the reaction instead of microwave heating. We furthermore describe solid phase extraction and HPLC procedures for quantitative determination of [ 18 F]altanserin and metabolites in plasma. The time course of arterial plasma activity with and without metabolite correction was determined. 90 min after bolus injection, 38.4% of total plasma activity derived from unchanged [ 18 F]altanserin. Statistical comparison of kinetic profiles of [ 18 F]altanserin metabolism in plasma samples collected in the course of two ongoing studies employing placebo, the serotonin releaser dexfenfluramine and the hallucinogen psilocybin, revealed the same tracer metabolism. We conclude that metabolite analysis for correction of individual plasma input functions used in tracer modeling is not necessary for [ 18 F]altanserin studies involving psilocybin or dexfenfluramine treatment

Microdose clinical trial: quantitative determination of nicardipine and prediction of metabolites in human plasma.

Science.gov (United States)

Yamane, Naoe; Takami, Tomonori; Tozuka, Zenzaburo; Sugiyama, Yuichi; Yamazaki, Akira; Kumagai, Yuji

2009-01-01

A sample treatment procedure and high-sensitive liquid chromatography/tandem mass spectrometry (LC/MS/MS) method for quantitative determination of nicardipine in human plasma were developed for a microdose clinical trial with nicardipine, a non-radioisotope labeled drug. The calibration curve was linear in the range of 1-500 pg/mL using 1 mL of plasma. Analytical method validation for the clinical dose, for which the calibration curve was linear in the range of 0.2-100 ng/mL using 20 microL of plasma, was also conducted. Each method was successfully applied to making determinations in plasma using LC/MS/MS after administration of a microdose (100 microg) and clinical dose (20 mg) to each of six healthy volunteers. We tested new approaches in the search for metabolites in plasma after microdosing. In vitro metabolites of nicardipine were characterized using linear ion trap-fourier transform ion cyclotron resonance mass spectrometry (LIT-FTICRMS) and the nine metabolites predicted to be in plasma were analyzed using LC/MS/MS. There is a strong possibility that analysis of metabolites by LC/MS/MS may advance to utilization in microdose clinical trials with non-radioisotope labeled drugs.

Fecal estradiol and progesterone metabolite levels in the three-toed sloth (Bradypus variegatus

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M. Mühlbauer

2006-02-01

Full Text Available The present study was carried out to assess the possibility of measuring fecal steroid hormone metabolites as a noninvasive technique for monitoring reproductive function in the three-toed sloth, Bradypus variegatus. Levels of the estradiol (E2 and progesterone (P4 metabolites were measured by radioimmunoassay in fecal samples collected over 12 weeks from 4 captive female B. variegatus sloths. The validation of the radioimmunoassay for evaluation of fecal steroid metabolites was carried out by collecting 10 blood samples on the same day as defecation. There was a significant direct correlation between the plasma and fecal E2 and P4 levels (P < 0.05, Pearson's test, thereby validating this noninvasive technique for the study of the estrous cycle in these animals. Ovulation was detected in two sloths (SL03 and SL04 whose E2 levels reached 2237.43 and 6713.26 pg/g wet feces weight, respectively, for over four weeks, followed by an increase in P4 metabolites reaching 33.54 and 3242.68 ng/g wet feces weight, respectively. Interestingly, SL04, which presented higher levels of E2 and P4 metabolites, later gave birth to a healthy baby sloth. The results obtained indicate that this is a reliable technique for recording gonadal steroid secretion and thereby reproduction in sloths.

Differences in metabolite profiles caused by pre-analytical blood processing procedures.

Science.gov (United States)

Nishiumi, Shin; Suzuki, Makoto; Kobayashi, Takashi; Yoshida, Masaru

2018-05-01

Recently, the use of metabolomic analysis of human serum and plasma for biomarker discovery and disease diagnosis in clinical studies has been increasing. The feasibility of using a metabolite biomarker for disease diagnosis is strongly dependent on the metabolite's stability during pre-analytical blood processing procedures, such as serum or plasma sampling and sample storage prior to centrifugation. However, the influence of blood processing procedures on the stability of metabolites has not been fully characterized. In the present study, we compared the levels of metabolites in matched human serum and plasma samples using gas chromatography coupled with mass spectrometry and liquid chromatography coupled with mass spectrometry. In addition, we evaluated the changes in plasma metabolite levels induced by storage at room temperature or at a cold temperature prior to centrifugation. As a result, it was found that 76 metabolites exhibited significant differences between their serum and plasma levels. Furthermore, the pre-centrifugation storage conditions significantly affected the plasma levels of 45 metabolites. These results highlight the importance of blood processing procedures during metabolome analysis, which should be considered during biomarker discovery and the subsequent use of biomarkers for disease diagnosis. Copyright © 2017 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Citalopram and escitalopram plasma drug and metabolite concentrations: genome-wide associations.

Science.gov (United States)

Ji, Yuan; Schaid, Daniel J; Desta, Zeruesenay; Kubo, Michiaki; Batzler, Anthony J; Snyder, Karen; Mushiroda, Taisei; Kamatani, Naoyuki; Ogburn, Evan; Hall-Flavin, Daniel; Flockhart, David; Nakamura, Yusuke; Mrazek, David A; Weinshilboum, Richard M

2014-08-01

Citalopram (CT) and escitalopram (S-CT) are among the most widely prescribed selective serotonin reuptake inhibitors used to treat major depressive disorder (MDD). We applied a genome-wide association study to identify genetic factors that contribute to variation in plasma concentrations of CT or S-CT and their metabolites in MDD patients treated with CT or S-CT. Our genome-wide association study was performed using samples from 435 MDD patients. Linear mixed models were used to account for within-subject correlations of longitudinal measures of plasma drug/metabolite concentrations (4 and 8 weeks after the initiation of drug therapy), and single-nucleotide polymorphisms (SNPs) were modelled as additive allelic effects. Genome-wide significant associations were observed for S-CT concentration with SNPs in or near the CYP2C19 gene on chromosome 10 (rs1074145, P = 4.1 × 10(-9) ) and with S-didesmethylcitalopram concentration for SNPs near the CYP2D6 locus on chromosome 22 (rs1065852, P = 2.0 × 10(-16) ), supporting the important role of these cytochrome P450 (CYP) enzymes in biotransformation of citalopram. After adjustment for the effect of CYP2C19 functional alleles, the analyses also identified novel loci that will require future replication and functional validation. In vitro and in vivo studies have suggested that the biotransformation of CT to monodesmethylcitalopram and didesmethylcitalopram is mediated by CYP isozymes. The results of our genome-wide association study performed in MDD patients treated with CT or S-CT have confirmed those observations but also identified novel genomic loci that might play a role in variation in plasma levels of CT or its metabolites during the treatment of MDD patients with these selective serotonin reuptake inhibitors. © 2014 The British Pharmacological Society.

Longitudinal Relationship between Plasma Reactive Oxygen Metabolites and Periodontal Condition in the Maintenance Phase of Periodontal Treatment

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Tatsuya Machida

2014-01-01

Full Text Available Aim. The present cohort study describes the longitudinal relationship between plasma oxidative status and periodontitis progression during the maintenance phase of treatment. Materials and Methods. Forty-five patients (mean age 58.8 years were monitored from 2008 to 2013. Periodontal conditions, including probing pocket depth (PPD and clinical attachment level (CAL, were recorded. Measurements of plasma reactive oxygen metabolites (ROM and biologic antioxidant potential (BAP were performed to evaluate plasma oxidative status. The patients were assigned into 2 groups as low and high plasma ROM level using a cut-off value which was median of plasma ROM level at baseline. Results. In the subjects with low plasma ROM level at baseline, changes in mean CAL were positively correlated with changes in plasma ROM levels, bleeding on probing, and plaque control record, but not with PPD. In the subjects with high plasma ROM at baseline, changes in CAL were significantly associated with only PPD at baseline. On the other hands there were no significant associations between changes in CAL and those in plasma BAP levels. Conclusions. When plasma ROM level in periodontitis patients was low, increases in plasma ROM level were associated with those in CAL during the maintenance phase of treatment.

Effect of Spirulina supplementation on plasma metabolites in crossbred and purebred Australian Merino lambs

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A.E.O. Malau-Aduli

2015-06-01

Full Text Available The effect of supplementing purebred and crossbred Merino lambs with Arthrospira platensis (Spirulina on plasma metabolite concentrations under pasture-based management system and the influences of sire breed and sex were investigated. A completely randomized experimental design balanced by 4 sire breeds (Merino, White Suffolk, Dorset and Black Suffolk, 3 Spirulina supplementation levels (0, 100 and 200 ml representing the control, low and high, respectively and 2 sexes (ewe and wether lambs was utilised. All lambs had ad libitum access to the basal diet of ryegrass pastures and barley. Lambs in the treatment groups were individually drenched daily with Spirulina prior to being released with the control group of lambs for grazing over a 6-week period following a 3-week adjustment phase. At the start and completion of the feeding trial, blood samples were centrifuged and plasma metabolites measured. Data were analysed with Spirulina supplementation level, sire breed, sex and their second-order interactions fitted as fixed effects and metabolite concentrations as dependent variables. Gamma-glutamyl transferase (GGT concentrations decreased (from 79.40 to 69.25 UI and glucose increased (from 3.81 to 4.19 mmol/L as the level of Spirulina supplementation increased from 0 ml in the control to 200 ml in the high treatment groups (P < 0.05. Lambs supplemented at low Spirulina levels had the highest creatinine concentrations (61.75 μmol/L. Interactions between sex and supplementation level significantly affected glucose, aspartate aminotransferase (AST and Mg concentrations (P < 0.05, while sire breed and supplementation level interactions influenced albumin to globulin (A/G ratio, creatinine and GGT concentrations. It was demonstrated that Spirulina supplementation does not negatively impact lamb health and productivity.

GMP-compliant radiosynthesis of [{sup 18}F]altanserin and human plasma metabolite studies

Energy Technology Data Exchange (ETDEWEB)

Hasler, F. [University Hospital of Psychiatry, Heffter Research Center, Zurich (Switzerland)], E-mail: fehasler@bli.uzh.ch; Kuznetsova, O.F.; Krasikova, R.N. [Institute of the Human Brain, Russian Academy of Science, St. Petersburg (Russian Federation); Cservenyak, T. [Center for Radiopharmaceutical Sciences of ETH, PSI and University Hospital Zurich (Switzerland); Quednow, B.B.; Vollenweider, F.X. [University Hospital of Psychiatry, Heffter Research Center, Zurich (Switzerland); Ametamey, S.M.; Westera, G. [Center for Radiopharmaceutical Sciences of ETH, PSI and University Hospital Zurich (Switzerland)

2009-04-15

[{sup 18}F]altanserin is the preferred radiotracer for in-vivo labeling of serotonin 2A receptors by positron emission tomography (PET). We report a modified synthesis procedure suited for reliable production of multi-GBq amounts of [{sup 18}F]altanserin useful for application in humans. We introduced thermal heating for drying of [{sup 18}F]fluoride as well as for the reaction instead of microwave heating. We furthermore describe solid phase extraction and HPLC procedures for quantitative determination of [{sup 18}F]altanserin and metabolites in plasma. The time course of arterial plasma activity with and without metabolite correction was determined. 90 min after bolus injection, 38.4% of total plasma activity derived from unchanged [{sup 18}F]altanserin. Statistical comparison of kinetic profiles of [{sup 18}F]altanserin metabolism in plasma samples collected in the course of two ongoing studies employing placebo, the serotonin releaser dexfenfluramine and the hallucinogen psilocybin, revealed the same tracer metabolism. We conclude that metabolite analysis for correction of individual plasma input functions used in tracer modeling is not necessary for [{sup 18}F]altanserin studies involving psilocybin or dexfenfluramine treatment.

Elevated prostaglandin E metabolites and abnormal plasma fatty acids at baseline in pediatric cystic fibrosis patients: a pilot study.

Science.gov (United States)

O'Connor, Michael Glenn; Thomsen, Kelly; Brown, Rebekah F; Laposata, Michael; Seegmiller, Adam

2016-10-01

Airway inflammation is a significant contributor to the morbidity of cystic fibrosis (CF) disease. One feature of this inflammation is the production of oxygenated metabolites, such as prostaglandins. Individuals with CF are known to have abnormal metabolism of fatty acids, typically resulting in reduced levels of linoleic acid (LA) and docosahexaenoic acid (DHA). This is a randomized, double-blind, cross-over clinical trial of DHA supplementation with endpoints of plasma fatty acid levels and prostaglandin E metabolite (PGE-M) levels. Patients with CF age 6-18 years with pancreatic insufficiency were recruited. Each participant completed 3 four-week study periods: DHA at two different doses (high dose and low dose) and placebo with a minimum 4 week wash-out between each period. Blood, urine, and exhaled breath condensate (EBC) were collected at baseline and after each study period for measurement of plasma fatty acids as well as prostaglandin E metabolites. Seventeen participants were enrolled, and 12 participants completed all 3 study periods. Overall, DHA supplementation was well tolerated without significant adverse events. There was a significant increase in plasma DHA levels with supplementation, but no significant change in arachidonic acid (AA) or LA levels. However, at baseline, AA levels were lower and LA levels were higher than previously reported for individuals with CF. Urine PGE-M levels were elevated in the majority of participants at baseline, and while levels decreased with DHA supplementation, they also decreased with placebo. Urine PGE-M levels are elevated at baseline in this cohort of pediatric CF patients, but there was no significant change in these levels with DHA supplementation compared to placebo. In addition, baseline plasma fatty acid levels for this cohort showed some difference to prior reports, including higher levels of LA and lower levels of AA, which may reflect changes in clinical care, and consequently warrants further

Effects of vanadium supplementation on performance, some plasma metabolites and glucose metabolism in Mahabadi goat kids.

Science.gov (United States)

Zarqami, A; Ganjkhanlou, M; Zali, A; Rezayazdi, K; Jolazadeh, A R

2018-04-01

This experiment was conducted to investigate the effects of vanadium (V) supplementation on performance, some plasma metabolites (cholesterol and triglycerides) and glucose metabolism in Mahabadi goat kids. Twenty-eight male kids (15 ± 2 kg body weight) were fed for 14 weeks in a completely randomized design with four treatments. Treatments were supplemented with 0 (control), 1, 2, and 3 mg V as vanadyl sulfate/animal/daily. On day 70, an intravenous glucose tolerance test (IVGTT) was conducted. Dry matter intake did not change by V supplementation, but adding V quadraticaly improved feed efficiency (p = .03) and tended to increase average daily gain (Quadratic, p = .09). Blood metabolites were unaffected by V supplementation, except for concentration of glucose in plasma, which decreased linearly as supplemental V level increased (p = .02). Plasma glucose concentrations at 15, 30, 45 and 60 min after glucose infusion were decreased in a quadratic fashion in response to increasing supplemental V level (p kids supplemented with 2 mg V had higher glucose clearance rate (K) and lower glucose half-life (T ½ ; p kids. © 2017 Blackwell Verlag GmbH.

Neuroactive steroid levels in plasma and cerebrospinal fluid of male multiple sclerosis patients.

Science.gov (United States)

Caruso, Donatella; Melis, Marta; Fenu, Giuseppe; Giatti, Silvia; Romano, Simone; Grimoldi, Maria; Crippa, Donatella; Marrosu, Maria Giovanna; Cavaletti, Guido; Melcangi, Roberto Cosimo

2014-08-01

Neuroactive steroid family includes molecules synthesized in peripheral glands (i.e., hormonal steroids) and directly in the nervous system (i.e., neurosteroids) which are key regulators of the nervous function. As already reported in clinical and experimental studies, neurodegenerative diseases affect the levels of neuroactive steroids. However, a careful analysis comparing the levels of these molecules in cerebrospinal fluid (CSF) and in plasma of multiple sclerosis (MS) patients is still missing. To this aim, the levels of neuroactive steroids were evaluated by liquid chromatography-tandem mass spectrometry in CSF and plasma of male adults affected by Relapsing-Remitting MS and compared with those collected in control patients. An increase in pregnenolone and isopregnanolone levels associated with a decrease in progesterone metabolites, dihydroprogesterone, and tetrahydroprogesterone was observed in CSF of MS patients. Moreover, an increase of 5α-androstane-3α,17β-diol and of 17β-estradiol levels associated with a decrease of dihydrotestosterone also occurred. In plasma, an increase in pregnenolone, progesterone, and dihydrotestosterone and a decrease in dihydroprogesterone and tetrahydroprogesterone levels were reported. This study shows for the first time that the levels of several neuroactive steroids, and particularly those of progesterone and testosterone metabolites, are deeply affected in CSF of relapsing-remitting MS male patients. We here demonstrated that, the cerebrospinal fluid and plasma levels of several neuroactive steroids are modified in relapsing remitting multiple sclerosis male patients. Interestingly, we reported for the first time that, the levels of progesterone and testosterone metabolites are deeply affected in cerebrospinal fluid. These findings may have an important relevance in therapeutic and/or diagnostic field of multiple sclerosis. © 2014 International Society for Neurochemistry.

Radioimmunossay of hormones and metabolites in blood serum and plasma

International Nuclear Information System (INIS)

Khare, G.P.

1978-01-01

Hormones or metabolites which are capable of producing antibodies can be detected and precisely quantitated by this method. Antibodies, to various hormones or metabolites whose assay is desired, are adsorbed onto commercially available imitation or cultured pearls. These pearls coated with antibody are contacted with a buffered reaction mixture containing blood serum or plasma specimen and respective radioactive antigen. The entire reaction is allowed to proceed for a time sufficient to form antigen (radioactive or non-radioactive)-antibody complex. These complexes on the pearls are washed and the total amount of radioactivity emanating from the complex is measured. This is indicative of the extent of binding of radioactive antigen and provides an indirect correlation of the amount of non-radioactive antigen present in the serum or plasma sample

The effect of casein, hydrolyzed casein and whey proteins on urinary and postprandial plasma metabolites in overweight and moderately obese human subjects

DEFF Research Database (Denmark)

Schmedes, Mette S; Bendtsen, Line Quist; Gomes, Sisse

2018-01-01

, hydrolyzed casein and whey proteins in overweight and moderately obese men and women by investigating select urinary and blood plasma metabolites. RESULTS: A total of 21 urinary and 23 plasma metabolites were identified by NMR spectroscopy. The postprandial plasma metabolites revealed a significant diet...

Aging effect on plasma metabolites and hormones concentrations in riding horses

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K. Kawasumi

2015-11-01

Full Text Available Age effects on plasma metabolites, hormone concentrations, and enzyme activities related to energy metabolism were investigated in 20 riding horses. Animals were divided into two groups: Young (3-8 years and aged (11-18 years. They were clinically healthy, and not obese. Plasma adiponectin (ADN concentrations in aged horses were significantly lower than those in young horses (mean±SE, 6.5±1.3 μg mL-1 vs, 10.9±1.7 μg mL-1, Mann-Whitney U test, respectively; P=0.0233. Plasma non-esterified fatty acid levels and Insulin and malondialdehyde concentrations in aged group tended to increase compared to those in young group although there were not significant differences statistically. In aged group, malate dehydrogenase/lactate dehydrogenase (M/L ratio, which is considered an energy metabolic indicator, did not change significantly compared to that in young group. Present data suggest that aging may negatively affect nutrition metabolism, but not induce remarkable changes in M/L ratio in riding horses.

Diets high in resistant starch increase plasma levels of trimethylamine-N-oxide, a gut microbiome metabolite associated with CVD risk

Energy Technology Data Exchange (ETDEWEB)

Bergeron, Nathalie; Williams, Paul T.; Lamendella, Regina; Faghihnia, Nastaran; Grube, Alyssa; Li, Xinmin; Wang, Zeneng; Knight, Rob; Jansson, Janet K.; Hazen, Stanley L.; Krauss, Ronald M.

2016-12-20

Production of trimethylamine-N-oxide (TMAO), a biomarker of CVD risk, is dependent on intestinal microbiota, but little is known of dietary conditions promoting changes in gut microbial communities. Resistant starches (RS) alter the human microbiota. We sought to determine whether diets varying in RS and carbohydrate (CHO) content affect plasma TMAO levels. We also assessed postprandial glucose and insulin responses and plasma lipid changes to diets high and low in RS. In a cross-over trial, fifty-two men and women consumed a 2-week baseline diet (41 percentage of energy (%E) CHO, 40 % fat, 19 % protein), followed by 2-week high- and low-RS diets separated by 2-week washouts. RS diets were assigned at random within the context of higher (51–53 %E)v. lower CHO (39–40 %E) intake. Measurements were obtained in the fasting state and, for glucose and insulin, during a meal test matching the composition of the assigned diet. With lower CHO intake, plasma TMAO, carnitine, betaine andγ-butyrobetaine concentrations were higher after the high-v. low-RS diet (P<0·01 each). These metabolites were not differentially affected by highv. low RS when CHO intake was high. Although the high-RS meal reduced postprandial insulin and glucose responses when CHO intake was low (P<0·01 each), RS did not affect fasting lipids, lipoproteins, glucose or insulin irrespective of dietary CHO content. In conclusion, a lower-CHO diet high in RS was associated with higher plasma TMAO levels. These findings, together with the absence of change in fasting lipids, suggest that short-term high-RS diets do not improve markers of cardiometabolic health.

Determination of epirubicin and its metabolite epirubicinol in saliva and plasma by HPLC

NARCIS (Netherlands)

Dodde, WIW; Maring, JG; Hendriks, G; Wachters, FM; Groen, HJM; de Vries, EGE; Uges, DRA

We present a high-performance liquid chromatography (HPLC) method suitable for the analysis of epirubicin and its metabolite epirubicinol in saliva and plasma. Preparation of saliva and plasma samples was performed by extraction of analytes with a chloroform: 2-propanol mixture (6:1, vol/vol) and

Simultaneous determination of clebopride and a major metabolite N-desbenzylclebopride in plasma by capillary gas chromatography-negative-ion chemical ionization mass spectrometry.

Science.gov (United States)

Robinson, P R; Jones, M D; Maddock, J; Rees, L W

1991-03-08

A procedure for the simultaneous assay of clebopride and its major metabolite N-desbenzylclebopride in plasma has been developed. The method utilizes capillary gas chromatography-negative-ion chemical ionization mass spectrometry with selected-ion monitoring of characteristic ions. Employing 2-ethoxy analogues as internal standards, the benzamides were extracted from basified plasma using dichloromethane. Subsequent reaction with heptafluorobutyric anhydride produced volatile mono- and diheptafluorobutyryl derivatives of clebopride and N-desbenzylclebopride, respectively. The methane negative-ion mass spectra of these derivatives exhibited intense high-mass ions ideal for specific quantitation of low levels in biological fluids. Using this procedure the recovery of the drug and metabolite from human plasma was found to be 84.4 +/- 1.5% (n = 3) and 77.4 +/- 4.7% (n = 3), respectively, at 0.5 ng/ml. Measurement of both compounds down to 0.10 ng/ml with a coefficient of variation of less than 10.5% is described. Plasma levels are reported in four volunteers up to 24 h following oral administration of 1 mg of clebopride malate salt.

Elevated Plasma Levels of 3-Hydroxyisobutyric Acid Are Associated With Incident Type 2 Diabetes

OpenAIRE

Mardinoglu A; Gogg S; Lotta LA; Stancáková A; Nerstedt A; Boren J; Blüher M; Ferrannini E; Langenberg C; Wareham NJ; Laakso M; Smith U

2018-01-01

Branched-chain amino acids (BCAAs) metabolite, 3-Hydroxyisobutyric acid (3-HIB) has been identified as a secreted mediator of endothelial cell fatty acid transport and insulin resistance (IR) using animal models. To identify if 3-HIB is a marker of human IR and future risk of developing Type 2 diabetes (T2D), we measured plasma levels of 3-HIB and associated metabolites in around 10,000 extensively phenotyped individuals. The levels of 3-HIB were increased in obesity but not robustly associat...

Reproducible diagnostic metabolites in plasma from typhoid fever patients in Asia and Africa.

Science.gov (United States)

Näsström, Elin; Parry, Christopher M; Vu Thieu, Nga Tran; Maude, Rapeephan R; de Jong, Hanna K; Fukushima, Masako; Rzhepishevska, Olena; Marks, Florian; Panzner, Ursula; Im, Justin; Jeon, Hyonjin; Park, Seeun; Chaudhury, Zabeen; Ghose, Aniruddha; Samad, Rasheda; Van, Tan Trinh; Johansson, Anders; Dondorp, Arjen M; Thwaites, Guy E; Faiz, Abul; Antti, Henrik; Baker, Stephen

2017-05-09

Salmonella Typhi is the causative agent of typhoid. Typhoid is diagnosed by blood culture, a method that lacks sensitivity, portability and speed. We have previously shown that specific metabolomic profiles can be detected in the blood of typhoid patients from Nepal (Näsström et al., 2014). Here, we performed mass spectrometry on plasma from Bangladeshi and Senegalese patients with culture confirmed typhoid fever, clinically suspected typhoid, and other febrile diseases including malaria. After applying supervised pattern recognition modelling, we could significantly distinguish metabolite profiles in plasma from the culture confirmed typhoid patients. After comparing the direction of change and degree of multivariate significance, we identified 24 metabolites that were consistently up- or down regulated in a further Bangladeshi/Senegalese validation cohort, and the Nepali cohort from our previous work. We have identified and validated a metabolite panel that can distinguish typhoid from other febrile diseases, providing a new approach for typhoid diagnostics.

[11C]Flumazenil metabolite measurement in plasma is not necessary for accurate brain benzodiazepine receptor quantification

International Nuclear Information System (INIS)

Sanabria-Bohorquez, S.M.; Veraart, C.; Labar, D.; Bol, A.; Volder, A.G. de; Michel, C.; Leveque, P.

2000-01-01

In this work, a mathematical correction for metabolites has been validated which estimates the relative amount of [ 11 C]flumazenil ([ 11 C]FMZ) in the total plasma curve from the tissue kinetic data without the need for direct metabolite measurement in blood plasma samples. Kinetic data were obtained using a 90-min three-injection protocol on five normal volunteers. First, the relative amount of [ 11 C]FMZ in plasma was modelled by a two-parameter exponential function. The parameters were estimated either directly by fitting this model to the blood plasma metabolite measurements, or indirectly from the simultaneous fitting of tissue time activity curves from several brain regions with a non-linear FMZ kinetic model. Second, the direct and indirect metabolite corrections were fixed and the FMZ compartmental parameters were determined on a regional basis in the brain. The validation was performed by comparing the regional values of benzodiazepine receptor density B max and equilibrium dissociation constant K d obtained with the direct metabolite correction with those values obtained with the indirect correction. For B max , the correlation coefficient r 2 was above 0.97 for all subjects and the slope values of the linear regression were within the interval [0.97, 1.2]. For K d , r 2 was above 0.96, and the slope values of the linear regression were within the interval [0.99, 1.1]. Simulation studies were performed in order to evaluate whether this metabolite correction method could be used in a clinical protocol where only a single [ 11 C]FMZ injection and a linear compartmental model are used. The resulting [ 11 C]FMZ distribution volume estimates were found to be linearly correlated with the true values, with r 2 =1.0 and a slope value of 1.1. The mathematical metabolite correction proved to be a feasible and reliable method to estimate the relative amount of [ 11 C]FMZ in plasma and the compartmental model parameters for three-injection protocols. Although

Protein precipitation: an expedient procedure for the routine analysis of the plasma metabolites of [123I]IBZM

International Nuclear Information System (INIS)

Zea-Ponce, Yolanda; Laruelle, Marc

1999-01-01

Plasma metabolite analysis of the single photon emission computed tomography (SPECT) D 2 /D 3 receptor radiotracer (S)(-)-N-[(1-ethyl-2-pyrrolidinyl)methyl]-2-hydroxy-3-[ 123 I] iodo-6-methoxyb enzamide ([ 123 I]IBZM) is needed for the equilibrium analysis of the SPECT data, in brain imaging studies involving bolus plus constant infusion paradigm. The purpose of these experiments was to find an appropriate procedure to expedite this analysis during routine determinations. The procedure was applied to the plasma analysis of 22 human subjects. Each plasma sample was subjected to acetonitrile protein precipitation. After separation of the pellet, the acetonitrile fraction contained 91%±2% (n=88) of the mixture of labeled metabolites and parent compound. The recovery coefficient of unmetabolized [ 123 I]IBZM determined with an standard plasma sample was 95%±2% (n=22). The percent parent compound present in the extracted fraction, measured by high performance liquid chromatography, was 16%±9% (n=85) and the percent metabolites was 84%±9% (n=85). Free fraction determination (f 1 , fraction of radiotracer unbound to protein), was 4%±0.8% (n=22). Free fraction of parent was 15%±8% (n=85). The results indicate that acetonitrile protein precipitation is an adequate method for the analysis of the [ 123 I]IBZM plasma metabolites

Plasma cortisol and metabolite level profiles in two isogenic strains of common carp during confinement

NARCIS (Netherlands)

Ruane, N.M.; Huisman, E.A.; Komen, J.

2001-01-01

A rapid increase in common carp Cyprinus carpio plasma cortisol levels was noted, in two experiments, after 30 mins of a 3 h net confinement, which was sustained while the fish were held in the nets. After release from the nets, cortisol levels returned to control values in 1 h. Plasma glucose and

Elevated Plasma Levels of 3-Hydroxyisobutyric Acid Are Associated With Incident Type 2 Diabetes

Directory of Open Access Journals (Sweden)

Adil Mardinoglu

2018-01-01

Full Text Available Branched-chain amino acids (BCAAs metabolite, 3-Hydroxyisobutyric acid (3-HIB has been identified as a secreted mediator of endothelial cell fatty acid transport and insulin resistance (IR using animal models. To identify if 3-HIB is a marker of human IR and future risk of developing Type 2 diabetes (T2D, we measured plasma levels of 3-HIB and associated metabolites in around 10,000 extensively phenotyped individuals. The levels of 3-HIB were increased in obesity but not robustly associated with degree of IR after adjusting for BMI. Nevertheless, also after adjusting for obesity and plasma BCAA, 3-HIB levels were associated with future risk of incident T2D. We also examined the effect of 3-HIB on fatty acid uptake in human cells and found that both HUVEC and human cardiac endothelial cells respond to 3-HIB whereas human adipose tissue-derived endothelial cells do not respond to 3-HIB. In conclusion, we found that increased plasma level of 3-HIB is a marker of future risk of T2D and 3-HIB may be important for the regulation of metabolic flexibility in heart and muscles.

Quantification of Stable Isotope Traces Close to Natural Enrichment in Human Plasma Metabolites Using Gas Chromatography-Mass Spectrometry.

Science.gov (United States)

Krämer, Lisa; Jäger, Christian; Trezzi, Jean-Pierre; Jacobs, Doris M; Hiller, Karsten

2018-02-14

Currently, changes in metabolic fluxes following consumption of stable isotope-enriched foods are usually limited to the analysis of postprandial kinetics of glucose. Kinetic information on a larger diversity of metabolites is often lacking, mainly due to the marginal percentage of fully isotopically enriched plant material in the administered food product, and hence, an even weaker 13 C enrichment in downstream plasma metabolites. Therefore, we developed an analytical workflow to determine weak 13 C enrichments of diverse plasma metabolites with conventional gas chromatography-mass spectrometry (GC-MS). The limit of quantification was increased by optimizing (1) the metabolite extraction from plasma, (2) the GC-MS measurement, and (3) most importantly, the computational data processing. We applied our workflow to study the catabolic dynamics of 13 C-enriched wheat bread in three human subjects. For that purpose, we collected time-resolved human plasma samples at 16 timepoints after the consumption of 13 C-labeled bread and quantified 13 C enrichment of 12 metabolites (glucose, lactate, alanine, glycine, serine, citrate, glutamate, glutamine, valine, isoleucine, tyrosine, and threonine). Based on isotopomer specific analysis, we were able to distinguish catabolic profiles of starch and protein hydrolysis. More generally, our study highlights that conventional GC-MS equipment is sufficient to detect isotope traces below 1% if an appropriate data processing is integrated.

Quantification of Stable Isotope Traces Close to Natural Enrichment in Human Plasma Metabolites Using Gas Chromatography-Mass Spectrometry

Science.gov (United States)

Krämer, Lisa; Jäger, Christian; Jacobs, Doris M.; Hiller, Karsten

2018-01-01

Currently, changes in metabolic fluxes following consumption of stable isotope-enriched foods are usually limited to the analysis of postprandial kinetics of glucose. Kinetic information on a larger diversity of metabolites is often lacking, mainly due to the marginal percentage of fully isotopically enriched plant material in the administered food product, and hence, an even weaker 13C enrichment in downstream plasma metabolites. Therefore, we developed an analytical workflow to determine weak 13C enrichments of diverse plasma metabolites with conventional gas chromatography-mass spectrometry (GC-MS). The limit of quantification was increased by optimizing (1) the metabolite extraction from plasma, (2) the GC-MS measurement, and (3) most importantly, the computational data processing. We applied our workflow to study the catabolic dynamics of 13C-enriched wheat bread in three human subjects. For that purpose, we collected time-resolved human plasma samples at 16 timepoints after the consumption of 13C-labeled bread and quantified 13C enrichment of 12 metabolites (glucose, lactate, alanine, glycine, serine, citrate, glutamate, glutamine, valine, isoleucine, tyrosine, and threonine). Based on isotopomer specific analysis, we were able to distinguish catabolic profiles of starch and protein hydrolysis. More generally, our study highlights that conventional GC-MS equipment is sufficient to detect isotope traces below 1% if an appropriate data processing is integrated. PMID:29443915

Quantification of Stable Isotope Traces Close to Natural Enrichment in Human Plasma Metabolites Using Gas Chromatography-Mass Spectrometry

Directory of Open Access Journals (Sweden)

Lisa Krämer

2018-02-01

Full Text Available Currently, changes in metabolic fluxes following consumption of stable isotope-enriched foods are usually limited to the analysis of postprandial kinetics of glucose. Kinetic information on a larger diversity of metabolites is often lacking, mainly due to the marginal percentage of fully isotopically enriched plant material in the administered food product, and hence, an even weaker 13C enrichment in downstream plasma metabolites. Therefore, we developed an analytical workflow to determine weak 13C enrichments of diverse plasma metabolites with conventional gas chromatography-mass spectrometry (GC-MS. The limit of quantification was increased by optimizing (1 the metabolite extraction from plasma, (2 the GC-MS measurement, and (3 most importantly, the computational data processing. We applied our workflow to study the catabolic dynamics of 13C-enriched wheat bread in three human subjects. For that purpose, we collected time-resolved human plasma samples at 16 timepoints after the consumption of 13C-labeled bread and quantified 13C enrichment of 12 metabolites (glucose, lactate, alanine, glycine, serine, citrate, glutamate, glutamine, valine, isoleucine, tyrosine, and threonine. Based on isotopomer specific analysis, we were able to distinguish catabolic profiles of starch and protein hydrolysis. More generally, our study highlights that conventional GC-MS equipment is sufficient to detect isotope traces below 1% if an appropriate data processing is integrated.

A prospective study of plasma vitamin D metabolites, vitamin D receptor polymorphisms, and prostate cancer.

Directory of Open Access Journals (Sweden)

Haojie Li

2007-03-01

Full Text Available Vitamin D insufficiency is a common public health problem nationwide. Circulating 25-hydroxyvitamin D3 (25[OH]D, the most commonly used index of vitamin D status, is converted to the active hormone 1,25 dihydroxyvitamin D3 (1,25[OH]2D, which, operating through the vitamin D receptor (VDR, inhibits in vitro cell proliferation, induces differentiation and apoptosis, and may protect against prostate cancer. Despite intriguing results from laboratory studies, previous epidemiological studies showed inconsistent associations of circulating levels of 25(OHD, 1,25(OH2D, and several VDR polymorphisms with prostate cancer risk. Few studies have explored the joint association of circulating vitamin D levels with VDR polymorphisms.During 18 y of follow-up of 14,916 men initially free of diagnosed cancer, we identified 1,066 men with incident prostate cancer (including 496 with aggressive disease, defined as stage C or D, Gleason 7-10, metastatic, and fatal prostate cancer and 1,618 cancer-free, age- and smoking-matched control participants in the Physicians' Health Study. We examined the associations of prediagnostic plasma levels of 25(OHD and 1,25(OH2D, individually and jointly, with total and aggressive disease, and explored whether relations between vitamin D metabolites and prostate cancer were modified by the functional VDR FokI polymorphism, using conditional logistic regression. Among these US physicians, the median plasma 25(OHD levels were 25 ng/ml in the blood samples collected during the winter or spring and 32 ng/ml in samples collected during the summer or fall. Nearly 13% (summer/fall to 36% (winter/spring of the control participants were deficient in 25(OHD (<20 ng/ml and 51% (summer/fall and 77% (winter/spring had insufficient plasma 25(OHD levels (<32 ng/ml. Plasma levels of 1,25(OH2D did not vary by season. Men whose levels for both 25(OHD and 1,25(OH2D were below (versus above the median had a significantly increased risk of aggressive

Plasma Metabolites Predict Severity of Depression and Suicidal Ideation in Psychiatric Patients-A Multicenter Pilot Analysis.

Science.gov (United States)

Setoyama, Daiki; Kato, Takahiro A; Hashimoto, Ryota; Kunugi, Hiroshi; Hattori, Kotaro; Hayakawa, Kohei; Sato-Kasai, Mina; Shimokawa, Norihiro; Kaneko, Sachie; Yoshida, Sumiko; Goto, Yu-Ichi; Yasuda, Yuka; Yamamori, Hidenaga; Ohgidani, Masahiro; Sagata, Noriaki; Miura, Daisuke; Kang, Dongchon; Kanba, Shigenobu

2016-01-01

Evaluating the severity of depression (SOD), especially suicidal ideation (SI), is crucial in the treatment of not only patients with mood disorders but also psychiatric patients in general. SOD has been assessed on interviews such as the Hamilton Rating Scale for Depression (HAMD)-17, and/or self-administered questionnaires such as the Patient Health Questionnaire (PHQ)-9. However, these evaluation systems have relied on a person's subjective information, which sometimes lead to difficulties in clinical settings. To resolve this limitation, a more objective SOD evaluation system is needed. Herein, we collected clinical data including HAMD-17/PHQ-9 and blood plasma of psychiatric patients from three independent clinical centers. We performed metabolome analysis of blood plasma using liquid chromatography mass spectrometry (LC-MS), and 123 metabolites were detected. Interestingly, five plasma metabolites (3-hydroxybutyrate (3HB), betaine, citrate, creatinine, and gamma-aminobutyric acid (GABA)) are commonly associated with SOD in all three independent cohort sets regardless of the presence or absence of medication and diagnostic difference. In addition, we have shown several metabolites are independently associated with sub-symptoms of depression including SI. We successfully created a classification model to discriminate depressive patients with or without SI by machine learning technique. Finally, we produced a pilot algorithm to predict a grade of SI with citrate and kynurenine. The above metabolites may have strongly been associated with the underlying novel biological pathophysiology of SOD. We should explore the biological impact of these metabolites on depressive symptoms by utilizing a cross species study model with human and rodents. The present multicenter pilot study offers a potential utility for measuring blood metabolites as a novel objective tool for not only assessing SOD but also evaluating therapeutic efficacy in clinical practice. In addition

Plasma Metabolites Predict Severity of Depression and Suicidal Ideation in Psychiatric Patients-A Multicenter Pilot Analysis.

Directory of Open Access Journals (Sweden)

Daiki Setoyama

Full Text Available Evaluating the severity of depression (SOD, especially suicidal ideation (SI, is crucial in the treatment of not only patients with mood disorders but also psychiatric patients in general. SOD has been assessed on interviews such as the Hamilton Rating Scale for Depression (HAMD-17, and/or self-administered questionnaires such as the Patient Health Questionnaire (PHQ-9. However, these evaluation systems have relied on a person's subjective information, which sometimes lead to difficulties in clinical settings. To resolve this limitation, a more objective SOD evaluation system is needed. Herein, we collected clinical data including HAMD-17/PHQ-9 and blood plasma of psychiatric patients from three independent clinical centers. We performed metabolome analysis of blood plasma using liquid chromatography mass spectrometry (LC-MS, and 123 metabolites were detected. Interestingly, five plasma metabolites (3-hydroxybutyrate (3HB, betaine, citrate, creatinine, and gamma-aminobutyric acid (GABA are commonly associated with SOD in all three independent cohort sets regardless of the presence or absence of medication and diagnostic difference. In addition, we have shown several metabolites are independently associated with sub-symptoms of depression including SI. We successfully created a classification model to discriminate depressive patients with or without SI by machine learning technique. Finally, we produced a pilot algorithm to predict a grade of SI with citrate and kynurenine. The above metabolites may have strongly been associated with the underlying novel biological pathophysiology of SOD. We should explore the biological impact of these metabolites on depressive symptoms by utilizing a cross species study model with human and rodents. The present multicenter pilot study offers a potential utility for measuring blood metabolites as a novel objective tool for not only assessing SOD but also evaluating therapeutic efficacy in clinical practice. In

10 CFR 26.133 - Cutoff levels for drugs and drug metabolites.

Science.gov (United States)

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Cutoff levels for drugs and drug metabolites. 26.133... § 26.133 Cutoff levels for drugs and drug metabolites. Subject to the provisions of § 26.31(d)(3)(iii), licensees and other entities may specify more stringent cutoff levels for drugs and drug metabolites than...

Blood sampling and hemolysis affect concentration of plasma metabolites

DEFF Research Database (Denmark)

Theil, Peter Kappel; Pedersen, Lene Juul; Jensen, Margit Bak

2012-01-01

design and blood was collected after restraint via vein puncture 1, 4, 11, and 23 h after morning feeding. Plasma samples were categorized as without or with minor or major hemolysis [clear (n = 218), yellow (n = 97), or red (n = 37)] upon centrifugation. Plasma NEFA (P ...Two experiments were carried out to reveal and quantify plasma metabolites that are sensitive to hemolysis and animal stress due to the blood sampling procedure (vein puncture vs. catheter). In Exp. 1, 48 sows were fed 4 diets either once (0800 h) or twice daily (0800 h and 1500 h) in a crossover......, a subset of samples from 24 sows fed twice daily in Exp. 1 was combined with data obtained from 30 sows sampled using jugular vein catheters. All sows in Exp. 2 were fed twice daily (0800 h and 1500 h) and blood samples collected repeatedly 1, 4, 11, and 23 h after morning feeding (other conditions were...

Profiling of plasma metabolites in canine oral melanoma using gas chromatography-mass spectrometry.

Science.gov (United States)

Kawabe, Mifumi; Baba, Yuta; Tamai, Reo; Yamamoto, Ryohei; Komori, Masayuki; Mori, Takashi; Takenaka, Shigeo

2015-08-01

Malignant melanoma is one of the most common and aggressive tumors in the oral cavity of dog. The tumor has a poor prognosis, and methods for diagnosis and prediction of prognosis after treatment are required. Here, we examined metabolite profiling using gas chromatography-mass spectrometry (GC-MS) for development of a discriminant model for evaluation of prognosis. Metabolite profiles were evaluated in healthy and melanoma plasma samples using orthogonal projection to latent structure using discriminant analysis (OPLS-DA). Cases that were predicted to be healthy using the OPLS discriminant model had no advanced lesions after radiation therapy. These results indicate that metabolite profiling may be useful in diagnosis and prediction of prognosis of canine malignant melanoma.

Untargeted metabolomic profiling plasma samples of patients with lung cancer for searching significant metabolites by HPLC-MS method

Science.gov (United States)

Dementeva, N.; Ivanova, K.; Kokova, D.; Kurzina, I.; Ponomaryova, A.; Kzhyshkowska, J.

2017-09-01

Lung cancer is one of the most common types of cancer leading to death. Consequently, the search and the identification of the metabolites associated with the risk of developing cancer are very valuable. For the purpose, untargeted metabolic profiling of the plasma samples collected from the patients with lung cancer (n = 100) and the control group (n = 100) was conducted. After sample preparation, the plasma samples were analyzed using LC-MS method. Biostatistics methods were applied to pre-process the data for elicitation of dominating metabolites which responded to the difference between the case and the control groups. At least seven significant metabolites were evaluated and annotated. The most part of identified metabolites are connected with lipid metabolism and their combination could be useful for follow-up studies of lung cancer pathogenesis.

Combined high-pressure liquid chromatography and radioimmunoassay method for the quantitation of Δ9-tetrahydrocannabinol and some of its metabolites in human plasma

International Nuclear Information System (INIS)

Williams, P.L.; Moffat, A.C.; King, L.J.

1978-01-01

A high-pressure liquid chromatography-radioimmunoassay (HPLC-RIA) method for the measurement of cannabinoid levels in plasma is described. The method is capable of quantifying 0.1 ng of a cannabinoid in 1 ml of plasma. The experimental procedure consists of an initial separation of cannabinoids in a plasma extract by HPLC followed by collection of the HPLC eluate and RIA. A chromatogram consisting of the cross-reacting cannabinoids in plasma may then be constructed. The plasma concentrations of cannabinoids with retention volumes equivalent to those of Δ 9 -terahydrocannabinol, cannabinol and mono-hydroxylated metabolites have been measured by this technique. (Auth.)

Chiral Plasma Pharmacokinetics of 3,4-Methylenedioxymethamphetamine and its Phase I and II Metabolites following Controlled Administration to Humans.

OpenAIRE

Steuer Andrea E; Schmidhauser Corina; Schmid Yasmin; Rickli Anna; Liechti Matthias E; Kraemer Thomas

2015-01-01

Generally, pharmacokinetic studies on 3,4-methylenedioxymethamphetamine (MDMA) in blood have been performed after conjugate cleavage, without taking into account that phase II metabolites represent distinct chemical entities with their own effects and stereoselective pharmacokinetics. The aim of the present study was to stereoselectively investigate the pharmacokinetics of intact glucuronide and sulfate metabolites of MDMA in blood plasma after a controlled single MDMA dose. Plasma samples fr...

10 CFR 26.163 - Cutoff levels for drugs and drug metabolites.

Science.gov (United States)

2010-01-01

... 10 Energy 1 2010-01-01 2010-01-01 false Cutoff levels for drugs and drug metabolites. 26.163... the Department of Health and Human Services § 26.163 Cutoff levels for drugs and drug metabolites. (a... testing of specimens to determine whether they are negative for the indicated drugs and drug metabolites...

The course of some bone remodelling plasma metabolites in healthy horses and in horses offered a calcium-deficient diet.

Science.gov (United States)

de Behr, V; Daron, D; Gabriel, A; Remy, B; Dufrasne, I; Serteyn, D; Istasse, L

2003-04-01

An inquiry was carried out to assess the concentrations of plasma metabolites related to bone remodelling in 21 saddle horses of Warmblood breed aged 4-26 years, five draught horses of Ardennes breed aged 4-10 years, and 10 Ardennes foals aged 9-11 months. They were fed according to normal feeding practice in Belgium. The changes in some bone remodelling plasma metabolite concentrations were studied when an unbalanced diet was offered and later corrected for four Warmblood horses. Bone formation was evaluated by bone alkaline phosphatase (BALP), total alkaline phosphatase (TALP) and osteocalcin (bone gla-protein, OC). Bone resorption was assessed by hydroxyproline (HYP). Total calcium, ionized calcium, phosphorus (P) and 25-hydroxyvitamin D3 [25-(OH)D] concentrations were more or less constant. The comparison of four bone remodelling factors between the Ardennes and Warmblood horses showed higher concentrations in the Ardennes breed. Bone marker concentrations decreased according to age. The correction of the unbalanced Ca : P diet induced inconsistent effects at plasma level. The interpretation of the different bone parameters appeared to be difficult if not associated with other parameters such as a complete anamnesis and clinical examination of the animal in addition to dietary evaluation.

Increased plasma concentrations of vitamin D metabolites and vitamin D binding protein in women using hormonal contraceptives: a cross-sectional study

DEFF Research Database (Denmark)

Liendgaard, Ulla Kristine Møller; við Streym, Susanna; Jensen, Lars Thorbjørn

2013-01-01

UNLABELLED: Use of hormonal contraceptives (HC) may influence total plasma concentrations of vitamin D metabolites. A likely cause is an increased synthesis of vitamin D binding protein (VDBP). Discrepant results are reported on whether the use of HC affects free concentrations of vitamin D...... metabolites. AIM: In a cross-sectional study, plasma concentrations of vitamin D metabolites, VDBP, and the calculated free vitamin D index in users and non-users of HC were compared and markers of calcium and bone metabolism investigated. RESULTS: 75 Caucasian women aged 25-35 years were included during......, parathyroid hormone, and calcitonin, p > 0.21) or bone metabolism (plasma bone specific alkaline phosphatase, osteocalcin, and urinary NTX/creatinine ratio) between groups. IN CONCLUSION: Use of HC is associated with 13%-25% higher concentrations of total vitamin D metabolites and VDBP. This however...

Tissue distribution of 14C-diazepam and its metabolites in rats

International Nuclear Information System (INIS)

Igari, Y.; Sugiyama, Y.; Sawada, Y.; Iga, T.; Hanano, M.

1982-01-01

We have kinetically investigated the tissue distribution of 14 C-diazepam and described the appearance and disappearance of its metabolites (3-hydroxydiazepam, desmethyldiazepam, and oxazepam) following a single iv injection of 14 C-diazepam into rats. Significant amounts of oxazepam were detected in plasma and various tissues in the rat, contrary to previous reports. Concentration-time profiles of diazepam in the main disposing organs (liver, kidney, and lung) and the other organs (brain, heart, and small intestine) indicated that diazepam was distributed rapidly to these organs. Concentration-time profiles of diazepam in the main tissues for drug distribution (skin and adipose) indicated that diazepam was slowly distributed to these tissues, whereas that in muscle, which is also responsible for drug distribution, indicated that diazepam was less rapidly distributed to this tissue. Metabolites appeared in plasma and various tissues or organs immediately after iv injection of diazepam. Metabolites levels in plasma and various tissues or organs were significantly lower than that of diazepam except for liver and small intestine, where metabolites levels were higher compared to that of diazepam and metabolites exhibited a considerable persistence

Influence of a ketogenic diet, fish-oil, and calorie restriction on plasma metabolites and lipids in C57BL/6J mice

Science.gov (United States)

2014-01-01

Background Diet therapies including calorie restriction, ketogenic diets, and fish-oil supplementation have been used to improve health and to treat a variety of neurological and non-neurological diseases. Methods We investigated the effects of three diets on circulating plasma metabolites (glucose and β-hydroxybutyrate), hormones (insulin and adiponectin), and lipids over a 32-day period in C57BL/6J mice. The diets evaluated included a standard rodent diet (SD), a ketogenic diet (KD), and a standard rodent diet supplemented with fish-oil (FO). Each diet was administered in either unrestricted (UR) or restricted (R) amounts to reduce body weight by 20%. Results The KD-UR increased body weight and glucose levels and promoted a hyperlipidemic profile, whereas the FO-UR decreased body weight and glucose levels and promoted a normolipidemic profile, compared to the SD-UR. When administered in restricted amounts, all three diets produced a similar plasma metabolite profile, which included decreased glucose levels and a normolipidemic profile. Linear regression analysis showed that circulating glucose most strongly predicted body weight and triglyceride levels, whereas calorie intake moderately predicted glucose levels and strongly predicted ketone body levels. Conclusions These results suggest that biomarkers of health can be improved when diets are consumed in restricted amounts, regardless of macronutrient composition. PMID:24910707

Plasma and serum from nonfasting men and women differ in their lipidomic profiles.

Science.gov (United States)

Ishikawa, Masaki; Tajima, Yoko; Murayama, Mayumi; Senoo, Yuya; Maekawa, Keiko; Saito, Yoshiro

2013-01-01

Biomarkers will play important roles in disease diagnosis, drug development, and the proper use of drugs. Blood is considered the best biofluid for biomarker research because it is easy to access and a wealth of data are available. However, previous studies revealed that several ionic metabolites showed different levels (including presence or absence) in plasma and serum. Thus, attention should be paid to selecting the best biofluid for biomarker exploration. Many lipid molecules have biological significance and thus would be candidate biomarkers. However, no comprehensive study revealing differences in lipid metabolite levels between plasma and serum has been undertaken. Furthermore, gender differences have not been reported. To clarify the difference in the levels of lipid metabolites between human plasma and serum from both genders, we performed lipid metabolomic analysis using liquid chromatography-mass spectrometry-based systems for phospholipids (PLs), lysoPLs, sphingomyelins, ceramides and oxidative fatty acids. Our results revealed that most of the lipid metabolites were present at similar levels in plasma and serum and in males and females. However, several oxidative fatty acid metabolites showed differences. Of the metabolites related to clotting processes, three showed higher levels in serum than in plasma, and three were detected only in serum. Furthermore, four metabolites were present at different levels between males and females, and two were detected only in males. Thus, attention should be paid to the selection of plasma or serum when utilizing these lipid metabolites as biomarkers.

Plasma oxalate levels in prevalent hemodialysis patients and potential implications for ascorbic acid supplementation.

Science.gov (United States)

Liu, Yuguan; Weisberg, Lawrence S; Langman, Craig B; Logan, Amanda; Hunter, Krystal; Prasad, Deepali; Avila, Jose; Venkatchalam, Thaliga; Berns, Jeffrey S; Handelman, Garry J; Sirover, William D

2016-10-01

Ascorbic acid (AA) supplementation may increase hemoglobin levels and decrease erythropoiesis-stimulating agent dose requirement in patients with end stage renal disease (ESRD). While plasma AA levels >100μM may be supratherapeutic, levels of at least 30μM may be needed to improve wound healing and levels may need to reach 70μM to optimize erythropoiesis. Of concern, oxalate (Ox), an AA metabolite, can accumulate in ESRD. Historically, if plasma Ox levels remain ≥30μM, oxalosis was of concern. Contemporary hemodialysis (HD) efficiencies may decrease the risk of oxalosis by maintaining pre-HD Ox levels HD patients. A prospective, observational study of 197 HD patients with pre-HD AA levels and pre-HD and post-HD Ox levels. Mean plasma Ox levels decreased 71% during the intradialytic period (22.3±11.1μM to 6.4±3.2μM, PHD plasma AA levels ≤100μM were not associated with a pre-HD plasma Ox level≥30μM, even if ferritin levels were increased. Pre-HD plasma Ox levels ≥20 or ≥30μM were not associated with lower cumulative 4-year survival. Pre-HD plasma AA levels up to 100μM in HD patients do not appear to be associated with an increased risk of developing secondary oxalosis, as the corresponding pre-HD plasma Ox level appears to be maintained at tolerable levels. Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Whey protein delays gastric emptying and suppresses plasma fatty acids and their metabolites compared to casein, gluten, and fish protein

DEFF Research Database (Denmark)

Stanstrup, Jan; Schou, Simon S; Holmer-Jensen, Jens

2014-01-01

), and cod (COD). Obese, nondiabetic subjects were included in the randomized, blinded, crossover meal study. Subjects ingested a high fat meal containing one of the four protein sources. Plasma samples were collected at five time points and metabolites analyzed using LC-Q-TOF-MS. In contrast to previous...... studies, the WI meal caused a decreased rate of gastric emptying compared to the other test meals. The WI meal also caused elevated levels of a number of amino acids, possibly stimulating insulin release leading to reduced plasma glucose. The WI meal also caused decreased levels of a number of fatty acids......, while the GLU meal caused elevated levels of a number of unidentified hydroxy fatty acids and dicarboxylic fatty acids. Also reported are a number of markers of fish intake unique to the COD meal....

Very low levels of 6-keto-prostaglandin F 1/sub α/ in human plasma

International Nuclear Information System (INIS)

Siess, W.; Dray, F.

1982-01-01

Two stable derivatives of PGI 2 , its nonenzymatic hydrolysis product (6-keto-PGF 1 /sub α/) and an enzymatic metabolite (6, 15-diketo-PGF 1 /sub α/) were determined in human plasma and urine. These compounds were measured by RIA after separation on rp-HPLC. Previous purification of the samples on rp=HPLC markedly enhanced the specificity of the RIA determinations of those compounds in plasma and urine. The PGI 2 derivative 6-keto-PGF 1 /sub α/ was detected in both plasma (4.7 +/- 3.2 pg/ml, mean +/- S.D., n = 34) and urine (166 +/- 61 pg/ml, n = 9). No gender differences of the plasma or urinary levels of 6-keto-PGF 1 /sub α/ were found. The PGI 2 metabolite 6, 15-diketo-PGF 1 /sub α/ was not measurable in plasma or urine ( 2 in man. When [ 3 H]PGI 2 was added to citrated blood immediately after venipuncture, it was recovered entirely as [ 3 H]6-keto-PGF 1 /sub α/ after rp-HPLC. Therefore any circulating PGI 2 would be measured as 6-keto-PGF 1 /sub α/ by our method. The results obtained suggest that PGI 2 could be present in human venous blood under physiological conditions, but only in very low concentrations

Plasma cortisol and faecal cortisol metabolites concentrations in stereotypic and non-stereotypic horses: do stereotypic horses cope better with poor environmental conditions?

Directory of Open Access Journals (Sweden)

Fureix Carole

2013-01-01

Full Text Available Abstract Background Stereotypic behaviours, i.e. repetitive behaviours induced by frustration, repeated attempts to cope and/or brain dysfunction, are intriguing as they occur in a variety of domestic and captive species without any clear adaptive function. Among the different hypotheses, the coping hypothesis predicts that stereotypic behaviours provide a way for animals in unfavourable environmental conditions to adjust. As such, they are expected to have a lower physiological stress level (glucocorticoids than non-stereotypic animals. Attempts to link stereotypic behaviours with glucocorticoids however have yielded contradictory results. Here we investigated correlates of oral and motor stereotypic behaviours and glucocorticoid levels in two large samples of domestic horses (NStudy1 = 55, NStudy2 = 58, kept in sub-optimal conditions (e.g. confinement, social isolation, and already known to experience poor welfare states. Each horse was observed in its box using focal sampling (study 1 and instantaneous scan sampling (study 2. Plasma samples (collected in study 1 but also non-invasive faecal samples (collected in both studies were retrieved in order to assess cortisol levels. Results Results showed that 1 plasma cortisol and faecal cortisol metabolites concentrations did not differ between horses displaying stereotypic behaviours and non-stereotypic horses and 2 both oral and motor stereotypic behaviour levels did not predict plasma cortisol or faecal cortisol metabolites concentrations. Conclusions Cortisol measures, collected in two large samples of horses using both plasma sampling as well as faecal sampling (the latter method minimizing bias due to a non-invasive sampling procedure, therefore do not indicate that stereotypic horses cope better, at least in terms of adrenocortical activity.

Measurement of concentrations of whole blood levels of choline, betaine, and dimethylglycine and their relations to plasma levels.

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Awwad, Hussain Mohamad; Kirsch, Susanne H; Geisel, Juergen; Obeid, Rima

2014-04-15

We aimed at developing a method for the measurement of choline and its metabolites in whole blood (WB). After an extraction step, quantification of choline, betaine, and dimethylglycine (DMG) was performed using ultra performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Plasma and WB metabolites were evaluated in a group of 61 elderly people. The calibration curves were linear (r(2)>0.997) for all compounds. The inter- and intra-assay coefficients of variation for all analytes were 90% and the relative matrix effect were ≤4.0%. The median concentrations of choline, betaine, and DMG were 11.3, 27.8, and 5.9μmol/L in plasma and 66.6, 165, and 13.7μmol/L in WB, respectively. There were positive correlations between WB and plasma markers; for choline (r=0.42), betaine (r=0.61), and DMG (r=0.56) (all p≤0.001). The concentrations of betaine in WB and plasma were significantly higher in men than in women. The concentrations of WB choline and DMG did not differ significantly according to sex. In conclusion, we have established a reliable method for measuring choline metabolites in WB. The concentrations of WB choline, betaine, and DMG seem to reflect intracellular concentrations of these metabolites. Copyright © 2014 Elsevier B.V. All rights reserved.

Cerebrospinal Fluid Levels of Monoamine Metabolites in the Epileptic Baboon

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Szabó, C. Ákos; Patel, Mayuri; Uteshev, Victor V.

2016-01-01

The baboon represents a natural model for genetic generalized epilepsy and sudden unexpected death in epilepsy (SUDEP). In this retrospective study, cerebrospinal fluid (CSF) monoamine metabolites and scalp electroencephalography (EEG) were evaluated in 263 baboons of a pedigreed colony. CSF monoamine abnormalities have been linked to reduced seizure thresholds, behavioral abnormalities and SUDEP in various animal models of epilepsy. The levels of 3-hydroxy-4-methoxyphenylglycol, 5-hydroxyindolacetic acid and homovanillic acid in CSF samples drawn from the cisterna magna were analyzed using high-performance liquid chromatography. These levels were compared between baboons with seizures (SZ), craniofacial trauma (CFT) and asymptomatic, control (CTL) baboons, between baboons with abnormal and normal EEG studies. We hypothesized that the CSF levels of major monoaminergic metabolites (i.e., dopamine, serotonin and norepinephrine) associate with the baboons’ electroclinical status and thus can be used as clinical biomarkers applicable to seizures/epilepsy. However, despite apparent differences in metabolite levels between the groups, usually lower in SZ and CFT baboons and in baboons with abnormal EEG studies, we did not find any statistically significant differences using a logistic regression analysis. Significant correlations between the metabolite levels, especially between 5-HIAA and HVA, were preserved in all electroclinical groups. While we were not able to demonstrate significant differences in monoamine metabolites in relation to seizures or EEG markers of epilepsy, we cannot exclude the monoaminergic system as a potential source of pathogenesis in epilepsy and SUDEP. A prospective study evaluating serial CSF monoamine levels in baboons with recently witnessed seizures, and evaluation of abnormal expression and function of monoaminergic receptors and transporters within epilepsy-related brain regions, may impact the electroclinical status. PMID:26924854

A single-run liquid chromatography mass spectrometry method to quantify neuroactive kynurenine pathway metabolites in rat plasma.

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Orsatti, Laura; Speziale, Roberto; Orsale, Maria Vittoria; Caretti, Fulvia; Veneziano, Maria; Zini, Matteo; Monteagudo, Edith; Lyons, Kathryn; Beconi, Maria; Chan, Kelvin; Herbst, Todd; Toledo-Sherman, Leticia; Munoz-Sanjuan, Ignacio; Bonelli, Fabio; Dominguez, Celia

2015-03-25

Neuroactive metabolites in the kynurenine pathway of tryptophan catabolism are associated with neurodegenerative disorders. Tryptophan is transported across the blood-brain barrier and converted via the kynurenine pathway to N-formyl-L-kynurenine, which is further degraded to L-kynurenine. This metabolite can then generate a group of metabolites called kynurenines, most of which have neuroactive properties. The association of tryptophan catabolic pathway alterations with various central nervous system (CNS) pathologies has raised interest in analytical methods to accurately quantify kynurenines in body fluids. We here describe a rapid and sensitive reverse-phase HPLC-MS/MS method to quantify L-kynurenine (KYN), kynurenic acid (KYNA), 3-hydroxy-L-kynurenine (3HK) and anthranilic acid (AA) in rat plasma. Our goal was to quantify these metabolites in a single run; given their different physico-chemical properties, major efforts were devoted to develop a chromatography suitable for all metabolites that involves plasma protein precipitation with acetonitrile followed by chromatographic separation by C18 RP chromatography, detected by electrospray mass spectrometry. Quantitation range was 0.098-100 ng/ml for 3HK, 9.8-20,000 ng/ml for KYN, 0.49-1000 ng/ml for KYNA and AA. The method was linear (r>0.9963) and validation parameters were within acceptance range (calibration standards and QC accuracy within ±30%). Copyright © 2015 Elsevier B.V. All rights reserved.

Milk decreases urinary excretion but not plasma pharmacokinetics of cocoa flavan-3-ol metabolites in humans.

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Mullen, William; Borges, Gina; Donovan, Jennifer L; Edwards, Christine A; Serafini, Mauro; Lean, Michael E J; Crozier, Alan

2009-06-01

Cocoa drinks containing flavan-3-ols are associated with many health benefits, and conflicting evidence exists as to whether milk adversely affects the bioavailability of flavan-3-ols. The objective was to determine the effect of milk on the bioavailability of cocoa flavan-3-ol metabolites. Nine human volunteers followed a low-flavonoid diet for 2 d before drinking 250 mL of a cocoa beverage, made with water or milk, that contained 45 micromol (-)-epicatechin and (-)-catechin. Plasma and urine samples were collected for 24 h, and flavan-3-ol metabolites were analyzed by HPLC with photodiode array and mass spectrometric detection. Milk affected neither gastric emptying nor the transit time through the small intestine. Two flavan-3-ol metabolites were detected in plasma and 4 in urine. Milk had only minor effects on the plasma pharmacokinetics of an (epi)catechin-O-sulfate and had no effect on an O-methyl-(epi)catechin-O-sulfate. However, milk significantly lowered the excretion of 4 urinary flavan-3-ol metabolites from 18.3% to 10.5% of the ingested dose (P = 0.016). Studies that showed protective effects of cocoa and those that showed no effect of milk on bioavailability used products that have a much higher flavan-3-ol content than does the commercial cocoa used in the present study. Most studies of the protective effects of cocoa have used drinks with a very high flavan-3-ol content. Whether similar protective effects are associated with the consumption of many commercial chocolate and cocoa products containing substantially lower amounts of flavan-3-ols, especially when absorption at lower doses is obstructed by milk, remains to be determined.

Determination of hexamethylmelamine and metabolites in plasma or serum by gas—liquid chromatography with a nitrogen-sensitive detector

NARCIS (Netherlands)

Hulshoff, A.; Neijt, J.P.; Smulders, C.F.A.; Loenen, A.C. van; Pinedo, H.M.

1980-01-01

A gas chromatographic method for the quantitative determination of hexamethylmelamine (HMM) and five of its metabolites in plasma (or serum) is described. After adjustment of the pH of the plasma sample to about 9.5, the compounds are extracted with chloroform containing 5% of isopropanol. Amyl

Metabolic fingerprinting of high-fat plasma samples processed by centrifugation- and filtration-based protein precipitation delineates significant differences in metabolite information coverage.

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Barri, Thaer; Holmer-Jensen, Jens; Hermansen, Kjeld; Dragsted, Lars O

2012-03-09

Metabolomics and metabolic fingerprinting are being extensively employed for improved understanding of biological changes induced by endogenous or exogenous factors. Blood serum or plasma samples are often employed for metabolomics studies. Plasma protein precipitation (PPP) is currently performed in most laboratories before LC-MS analysis. However, the impact of fat content in plasma samples on metabolite coverage has not previously been investigated. Here, we have studied whether PPP procedures influence coverage of plasma metabolites from high-fat plasma samples. An optimized UPLC-QTOF/MS metabolic fingerprinting approach and multivariate modeling (PCA and OPLS-DA) were utilized for finding characteristic metabolite changes induced by two PPP procedures; centrifugation and filtration. We used 12-h fasting samples and postprandial samples collected at 2h after a standardized high-fat protein-rich meal in obese non-diabetic subjects recruited in a dietary intervention. The two PPP procedures as well as external and internal standards (ISs) were used to track errors in response normalization and quantification. Remarkably and sometimes uniquely, the fPPP, but not the cPPP approach, recovered not only high molecular weight (HMW) lipophilic metabolites, but also small molecular weight (SMW) relatively polar metabolites. Characteristic SMW markers of postprandial samples were aromatic and branched-chain amino acids that were elevated (p<0.001) as a consequence of the protein challenge. In contrast, some HMW lipophilic species, e.g. acylcarnitines, were moderately lower (p<0.001) in postprandial samples. LysoPCs were largely unaffected. In conclusion, the fPPP procedure is recommended for processing high-fat plasma samples in metabolomics studies. While method improvements presented here were clear, use of several ISs revealed substantial challenges to untargeted metabolomics due to large and variable matrix effects. Copyright © 2012 Elsevier B.V. All rights reserved.

Monitoring nicotine intake from e-cigarettes: measurement of parent drug and metabolites in oral fluid and plasma.

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Papaseit, Esther; Farré, Magí; Graziano, Silvia; Pacifici, Roberta; Pérez-Mañá, Clara; García-Algar, Oscar; Pichini, Simona

2017-03-01

Electronic cigarettes (e-cig) known as electronic nicotine devices recently gained popularity among smokers. Despite many studies investigating their safety and toxicity, few examined the delivery of e-cig-derived nicotine and its metabolites in alternative biological fluids. We performed a randomized, crossover, and controlled clinical trial in nine healthy smokers. Nicotine (NIC), cotinine (COT), and trans-3'-hydroxycotinine (3-HCOT) were measured in plasma and oral fluid by liquid chromatography-tandem mass spectrometry after consumption of two consecutive e-cig administrations or two consecutive tobacco cigarettes. NIC and its metabolites were detected both in oral fluid and plasma following both administration conditions. Concentrations in oral fluid resulted various orders of magnitude higher than those observed in plasma. Oral fluid concentration of tobacco cigarette and e-cig-derived NIC peaked at 15 min after each administration and ranged between 1.0 and 1396 μg/L and from 0.3 to 860 μg/L; those of COT between 52.8 and 110 μg/L and from 33.8 to 94.7 μg/L; and those of 3-HCOT between 12.4 and 23.5 μg/L and from 8.5 to 24.4 μg/L. The oral fluid to plasma concentration ratio of both e-cig- and tobacco cigarette-derived NIC peaked at 15 min after both administrations and correlated with oral fluid NIC concentration. The obtained results support the measurement of NIC and metabolites in oral fluid in the assessment of intake after e-cig use and appear to be a suitable alternative to plasma when monitoring nicotine delivery from e-cig for clinical and toxicological studies.

Sensitivity and proportionality assessment of metabolites from microdose to high dose in rats using LC-MS/MS.

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Ni, Jinsong; Ouyang, Hui; Seto, Carmai; Sakuma, Takeo; Ellis, Robert; Rowe, Josh; Acheampong, Andrew; Welty, Devin; Szekely-Klepser, Gabriella

2010-03-01

The objective of this study was to evaluate the sensitivity requirement for LC-MS/MS as an analytical tool to characterize metabolites in plasma and urine at microdoses in rats and to investigate proportionality of metabolite exposure from a microdose of 1.67 µg/kg to a high dose of 5000 µg/kg for atorvastatin, ofloxacin, omeprazole and tamoxifen. Only the glucuronide metabolite of ofloxacin, the hydroxylation metabolite of omeprazole and the hydration metabolite of tamoxifen were characterized in rat plasma at microdose by LC-MS/MS. The exposure of detected metabolites of omeprazole and tamoxifen appeared to increase in a nonproportional manner with increasing doses. Exposure of ortho- and para-hydroxyatorvastatin, but not atorvastatin and lactone, increased proportionally with increasing doses. LC-MS/MS has demonstrated its usefulness for detecting and characterizing the major metabolites in plasma and urine at microdosing levels in rats. The exposure of metabolites at microdose could not simply be used to predict their exposure at higher doses.

Association between Metabolite Profiles, Metabolic Syndrome and Obesity Status

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Bénédicte Allam-Ndoul

2016-05-01

Full Text Available Underlying mechanisms associated with the development of abnormal metabolic phenotypes among obese individuals are not yet clear. Our aim is to investigate differences in plasma metabolomics profiles between normal weight (NW and overweight/obese (Ov/Ob individuals, with or without metabolic syndrome (MetS. Mass spectrometry-based metabolite profiling was used to compare metabolite levels between each group. Three main principal components factors explaining a maximum of variance were retained. Factor 1’s (long chain glycerophospholipids metabolite profile score was higher among Ov/Ob with MetS than among Ov/Ob and NW participants without MetS. This factor was positively correlated to plasma total cholesterol (total-C and triglyceride levels in the three groups, to high density lipoprotein -cholesterol (HDL-C among participants without MetS. Factor 2 (amino acids and short to long chain acylcarnitine was positively correlated to HDL-C and negatively correlated with insulin levels among NW participants. Factor 3’s (medium chain acylcarnitines metabolite profile scores were higher among NW participants than among Ov/Ob with or without MetS. Factor 3 was negatively associated with glucose levels among the Ov/Ob with MetS. Factor 1 seems to be associated with a deteriorated metabolic profile that corresponds to obesity, whereas Factors 2 and 3 seem to be rather associated with a healthy metabolic profile.

Levels of caffeine and its metabolites among U.S. smokers and nonsmokers.

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Jain, Ram B

2015-03-01

Data from National Health and Nutrition Examination Survey for the years 2009-2010 were used to estimate the levels of caffeine and 14 of its metabolite among U.S. smokers and nonsmokers after adjustments were made for other factors that affect observed caffeine levels. In this study, when adjusted for daily caffeine intake, adjusted levels (AGM) of caffeine and its metabolites were not found to be statistically significantly different between smokers and nonsmokers. AGMs for caffeine and all of its metabolites were found to be statistically significantly higher (p whites > Hispanics > non-Hispanic blacks and most of the differences were statistically significant, at least between non-Hispanic whites and non-Hispanic blacks (p < 0.01). In general, there was a statistically significant positive association between the levels of caffeine and its metabolites and body mass index as well as daily caffeine intake. However, the levels of 7-methylxanthine were negatively associated with body mass index. Copyright © 2015 Elsevier B.V. All rights reserved.

Determination of the 4-monohydroxy metabolites of perhexiline in human plasma, urine and liver microsomes by liquid chromatography.

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Davies, Benjamin J; Herbert, Megan K; Coller, Janet K; Somogyi, Andrew A; Milne, Robert W; Sallustio, Benedetta C

2006-11-07

The use of perhexiline (PHX) is limited by hepatic and neurological toxicity associated with elevated concentrations in plasma that are the result of polymorphism of the cytochrome P450 2D6 isoform (CYP2D6). PHX is cleared by hepatic oxidation that produces three 4-monohydroxy metabolites: cis-OH-PHX, trans1-OH-PHX and trans2-OH-PHX. The current study describes an HPLC-fluorescent method utilising pre-column derivatization with dansyl chloride. Following derivatization, the metabolites were resolved on a C18 column with a gradient elution using a mobile phase composed of methanol and water. The method described is suitable for the quantification of the metabolites in human plasma and urine following clinical doses and for kinetic studies using human liver microsomes. The method demonstrates sufficient sensitivity, accuracy and precision between 5.0 and 0.01, 50.0 and 0.2 and 1.0 and 0.005 mg/l in human plasma, urine and liver microsomes, respectively, with intra-assay coefficients of variation and bias D6 extensive metaboliser (EM) patients at steady state with respect to PHX dosing determined that the mean (+/-S.D.) renal clearances of trans1-OH-PHX and cis-OH-PHX were 1.58+/-0.35 and 0.16+/-0.06l/h, respectively. The mean (+/-S.D.) dose recovered in urine as free and glucuronidated 4-monohydroxy PHX metabolites was 20.6+/-11.6%.

Lactate turnover in fast-moving vertebrates: The control of plasma metabolite fluxes

Energy Technology Data Exchange (ETDEWEB)

Weber, J.M.

1987-01-01

The goals of this thesis were: (1) to investigate the major factors involved in the regulation of plasma metabolite turnover at the whole-organism level-using lactate as a model, and (2) to determine whether endurance-adapted animals can support higher lactate turnover rates than sedentary animals. Lactate turnover was measured by bolus injection of (U{sup {minus}14}C)lacetate in skipjack tuna, Katsuwonus pelamis, and in thoroughbred race horses, Equus caballus. In tuna, turnover rates ranged from 112 to 431 umol min{sup {minus}1} kg{sup {minus}1}, and they were positively correlated with (lactate). These rates were higher than expected for a mammal of equivalent size. Plots of resting lactate and glucose turnover rates vs body mass on a log-log scale were linear for a wide range mammalian body sizes, and they showed the same slope as the classic body mass vs metabolic rate relationship.

Time-series responses of swine plasma metabolites to ingestion of diets containing myo-inositol or phytase.

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Cowieson, Aaron J; Roos, Franz F; Ruckebusch, Jean-Paul; Wilson, Jonathan W; Guggenbuhl, Patrick; Lu, Hang; Ajuwon, Kolapo M; Adeola, Olayiwola

2017-12-01

The effect of the ingestion of diets containing either myo-inositol or exogenous phytase on plasma metabolites was examined using 29 kg barrows. The diets were: control (maize, soya, rapeseed, rice bran), control plus 2 g/kg myo-inositol, control plus 1000 phytase units (FYT)/kg or 3000 FYT/kg exogenous phytase. Pigs were housed in a PigTurn device and blood was collected, from jugular catheters, via an automated system at -30, (30 min before feeding), 0, 15, 30, 45, 60, 90, 120, 150, 180, 240, 300 and 360 min post-feeding. The addition of 2 g/kg myo-inositol to the basal diet resulted in an increase in plasma myo-inositol concentration that was evident 45-60 min after diet introduction and persisted to 360 min post-feeding. Similarly, supplementation of the basal diet with either 1000 or 3000 FYT/kg exogenous phytase resulted in an increase in plasma myo-inositol concentration that was still rising 360 min post-feeding. Plasma P concentration was increased over time by the addition of 1000 and 3000 FYT/kg phytase, but not by the addition of myo-inositol. Other plasma metabolites examined were not affected by dietary treatment. It can be concluded that oral delivery of myo-inositol results in rapid increase in plasma myo-inositol concentrations that peak approximately 45-60 min after feeding. Use of supplemental phytase achieves similar increases in myo-inositol concentration in plasma but the appearance is more gradual. Furthermore, supplementation of pig diets with exogenous phytase results in rapid appearance of P in plasma that may be sustained over time relative to diets with no added phytase.

Rapid solid-phase extraction method to quantify [11C]-verapamil, and its [11C]-metabolites, in human and macaque plasma

International Nuclear Information System (INIS)

Unadkat, Jashvant D.; Chung, Francisco; Sasongko, Lucy; Whittington, Dale; Eyal, Sara; Mankoff, David; Collier, Ann C.; Muzi, Mark; Link, Jeanne

2008-01-01

Introduction: P-glycoprotein (P-gp), an efflux transporter, is a significant barrier to drug entry into the brain and the fetus. The positron emission tomography (PET) ligand, [ 11 C]-verapamil, has been used to measure in vivo P-gp activity at various tissue-blood barriers of humans and animals. Since verapamil is extensively metabolized in vivo, it is important to quantify the extent of verapamil metabolism in order to interpret such P-gp activity. Therefore, we developed a rapid solid-phase extraction (SPE) method to separate, and then quantify, verapamil and its radiolabeled metabolites in plasma. Methods: Using high-performance liquid chromatography (HPLC), we established that the major identifiable circulating radioactive metabolite of [ 11 C]-verapamil in plasma of humans and the nonhuman primate, Macaca nemestrina, was [ 11 C]-D-617/717. Using sequential and differential pH elution on C 8 SPE cartridges, we developed a rapid method to separate [ 11 C]-verapamil and [ 11 C]-D-617/717. Recovery was measured by spiking the samples with the corresponding nonradioactive compounds and assaying these compounds by HPLC. Results: Verapamil and D-617/717 recovery with the SPE method was >85%. When the method was applied to PET studies in humans and nonhuman primates, significant plasma concentration of D-617/717 and unknown polar metabolite(s) were observed. The SPE and the HPLC methods were not significantly different in the quantification of verapamil and D-617/717. Conclusions: The SPE method simultaneously processes multiple samples in less than 5 min. Given the short half-life of [ 11 C], this method provides a valuable tool to rapidly determine the concentration of [ 11 C]-verapamil and its [ 11 C]-metabolites in human and nonhuman primate plasma

Plasma biomarker of dietary phytosterol intake.

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Xiaobo Lin

Full Text Available Dietary phytosterols, plant sterols structurally similar to cholesterol, reduce intestinal cholesterol absorption and have many other potentially beneficial biological effects in humans. Due to limited information on phytosterol levels in foods, however, it is difficult to quantify habitual dietary phytosterol intake (DPI. Therefore, we sought to identify a plasma biomarker of DPI.Data were analyzed from two feeding studies with a total of 38 subjects during 94 dietary periods. DPI was carefully controlled at low, intermediate, and high levels. Plasma levels of phytosterols and cholesterol metabolites were assessed at the end of each diet period. Based on simple ordinary least squares regression analysis, the best biomarker for DPI was the ratio of plasma campesterol to the endogenous cholesterol metabolite 5-α-cholestanol (R2 = 0.785, P 0.600; P < 0.01.The ratio of plasma campesterol to the coordinately regulated endogenous cholesterol metabolite 5-α-cholestanol is a biomarker of dietary phytosterol intake. Conversely, plasma phytosterol levels alone are not ideal biomarkers of DPI because they are confounded by large inter-individual variation in absorption and turnover of non-cholesterol sterols. Further work is needed to assess the relation between non-cholesterol sterol metabolism and associated cholesterol transport in the genesis of coronary heart disease.

Urinary metabolite levels and symptoms in Filipino workers using organic solvents.

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Cucueco, M T; Espinosa, N C; Villanueva, M B; Castro, F T; Sison, S Y; Ortega, V S; Hisanaga, N

1993-01-01

To compare symptoms with urinary metabolite levels, 900 workers from 7 organic solvent-using industries were studied. Urinary metabolites were determined using a high performance liquid chromatograph. Urinary hippuric acid concentrations exceeding the reference value (2.5 g/g creatinine) were found in 78 (8.7%) workers. However, only 3 (0.3%) and 1 (0.1%) of the participants exceeded the reference value for mandelic (0.8 g/g creatinine) and total methylhippuric acid (1.5 g/g creatinine), respectively. The sum of the values of the ratio of measured urinary metabolite concentration to the corresponding ACGIH's biological exposure indices (BEI) [(HA/BEI of HA + MHA/BEI of MHA + MA/BEI of MA)] exceeded 1.0 in 166 (18.4%) workers. Majority of them were from the footwear manufacturing industry (63/129 or 49.2%). Questionnaire interviews were also administered to determine the prevalence of symptoms while at work (acute symptoms) or within the past 6 months (chronic symptoms). Urinary metabolite levels of individual and mixed solvents were compared with the symptoms of all workers. Analysis using Spearman's rank correlation showed in workers whose urinary hippuric acid exceeded 3.75 g/g creatine (1.5 x BEI), significant correlation between their hippuric acid levels and subjective complaints. Workers whose sum of the values of the ratio of measured urinary metabolite concentration to corresponding BEI exceeded 1.5 were selected and comparing this level with their symptoms, significant correlation was also noted in some complaints.

Simvastatin (SV) metabolites in mouse tissues

International Nuclear Information System (INIS)

Duncan, C.A.; Vickers, S.

1990-01-01

SV, a semisynthetic analog of lovastatin, is hydrolyzed in vivo to its hydroxy acid (SVA), a potent inhibitor of HMG CoA reductase (HR). Thus SV lowers plasma cholesterol. SV is a substrate for mixed function oxidases whereas SVA undergoes lactonization and β-oxidation. Male CD-1 mice were dosed orally with a combination of ( 14 C)SV and ( 3 H)SVA at 25 mg/kg of each, bled and killed at 0.5, 2 and 4 hours. Labeled SV, SVA, 6'exomethylene SV (I), 6'CH 2 OH-SV (II), 6'COOH-SV (III) and a β-oxidized metabolite (IV) were assayed in liver, bile, kidneys, testes and plasma by RIDA. Levels of potential and active HR inhibitors in liver were 10 to 40 fold higher than in other tissues. II and III, in which the configuration at 6' is inverted, may be 2 metabolites of I. Metabolites I-III are inhibitors of HR in their hydroxy acid forms. Qualitatively ( 14 C)SV and ( 3 H)SVA were metabolized similarly (consistent with their proposed interconversion). However 3 H-SVA, I-III (including hydroxy acid forms) achieved higher concentrations than corresponding 14 C compounds (except in gall bladder bile). Major radioactive metabolites in liver were II-IV (including hydroxy acid forms). These metabolites have also been reported in rat tissues. In bile a large fraction of either label was unidentified polar metabolites. The presence of IV indicated that mice (like rats) are not good models for SV metabolism in man

Plasma pharmacokinetics of catechin metabolite 4'-O-Me-EGC in healthy humans.

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Renouf, Mathieu; Redeuil, Karine; Longet, Karin; Marmet, Cynthia; Dionisi, Fabiola; Kussmann, Martin; Williamson, Gary; Nagy, Kornél

2011-10-01

Tea is an infusion of the leaves of the Camellia sinensis plant and is the most widely consumed beverage in the world after water. Green tea contains significant amounts of polyphenol catechins and represents a promising dietary component to maintain health and well-being. Epidemiological studies indicate that polyphenol intake may have potential health benefits, such as, reducing the incidence of coronary heart disease, diabetes and cancer. While bioavailability of green tea bioactives is fairly well understood, some gaps still remain to be filled, especially the identification and quantification of conjugated metabolites in plasma, such as, sulphated, glucuronidated or methylated compounds. In the present study, we aimed to quantify the appearance of green tea catechins in plasma with particular emphasis on their methylated forms. After feeding 400 mL of green tea, 1.25% infusion to 9 healthy subjects, we found significant amounts of EC, EGC and EGCg in plasma as expected. EGC was the most bioavailable catechin, and its methylated form (4'-O-Me-EGC) was also present in quantifiable amounts. Its kinetics followed that of its parent compound. However, the relative amount of the methylated form of EGC was lower than that of the parent compound, an important aspect which, in the literature, has been controversial so far. The quantitative results presented in our study were confirmed by co-chromatography and accurate mass analysis of the respective standards. We show that the relative abundance of 4'-O-Me-EGC is ~40% compared to the parent EGC. 4'-O-Me-EGC is an important metabolite derived from catechin metabolism. Its presence in significant amounts should not be overlooked when assessing human bioavailability of green tea.

Effects of vitamin D3 supplementation and UVb exposure on the growth and plasma concentration of vitamin D3 metabolites in juvenile bearded dragons (Pogona vitticeps)

NARCIS (Netherlands)

Oonincx, D.G.A.B.; Stevens, Y.; Borne, van den J.J.G.C.; Leeuwen, van J.P.T.M.; Hendriks, W.H.

2010-01-01

The effectiveness of dietary vitamin D3 and UVb exposure on plasma vitamin D metabolites in growing bearded dragons (Pogona vitticeps) was studied. A total of 84 (40 males and 44 females) newly hatched bearded dragons were allocated to six levels of oral vitamin D3 supplementation (0 to 400%) or six

Serotonin syndrome following sibutramine poisoning in a child, with sequential quantification of sibutramine and its primary and secondary amine metabolites in plasma.

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Bucaretchi, Fábio; de Capitani, Eduardo Mello; Mello, Sueli Moreira; Lanaro, Rafael; Barros, Roberta F; Fernandes, Luciane C R; da Costa, José Luiz; Hyslop, Stephen

2009-07-01

To report a case of serotonin syndrome (SS) after sibutramine overdose in a child. A 4-year-old girl was admitted 25 h after accidentally ingesting approximately 27 pills of sibutramine (15 mg, approximately 23 mg/kg). The child developed clinical features suggestive of SS, including diaphoresis, tachycardia, hypertension, agitation, insomnia, incoordination, hypertonia (lower limbs > upper limbs), and hallucinations. Serum creatine phosphokinase levels reached a peak on day 3 (2,577 U/L, reference value sibutramine and the active metabolites, M1 (mono-desmethyl sibutramine) and M2 (di-desmethyl sibutramine), by liquid chromatography/electrospray ionization tandem mass spectrometry in six sequential samples collected from 25 to 147 h post-ingestion revealed a nonlinear decrease in the log-scale plasma concentrations. Treatment was only supportive and involved prolonged sedation to control the agitation, sleeplessness, and hypertension; no cyproheptadine was used. The patient was discharged on day 6 and follow-up revealed no sequelae. To our knowledge, this is the first report of SS after sibutramine overdose in a child, with sequential monitoring of the plasma levels of the drug and its two active metabolites. The growing consumption of weight reducing pills may increase the risk of unintentional acute toxic exposures in children.

Low plasma cortisol and fecal cortisol metabolite measures as indicators of compromised welfare in domestic horses (Equus caballus.

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Jodi Pawluski

Full Text Available The hypothalamic-pituitary-adrenal (HPA axis response to chronic stress is far from straight forward, particularly with regards to animal welfare. There are reports of no effect as well as both decreases and increases in cortisol after chronic stressors. Therefore, the first aim of the present study was to determine how measures of compromised welfare, such as chronic pain and haematological anomalies, related to cortisol levels in domestic horses (Equus caballus. Domestic horses are an informative model to investigate the impact of chronic stress (due to environment, pain, work, housing conditions… on the HPA axis. The second aim was to determine whether levels of fecal cortisol metabolites (FCM may be used as an indicator of welfare measures. The present study used fifty-nine horses (44 geldings and 15 mares, from three riding centres in Brittany, France. The primary findings show that horses whose welfare was clearly compromised (as indicated by an unusual ears backward position, presence of vertebral problems or haematological anomalies, e.g. anaemia also had lower levels of both FCM and plasma cortisol. This work extends our previous findings showing that withdrawn postures, indicators of depressive-like behavior in horses, are associated with lower plasma cortisol levels. We also found that evening plasma cortisol levels positively correlated with FCM levels in horses. Future research aims to determine the extent to which factors of influence on welfare, such as living conditions (e.g. single stalls versus group housing in pasture or paddocks, early life factors, and human interaction, act as mediators of cortisol levels in horses.

The influence of feeding and fasting on plasma metabolites in the dogfish shark (Squalus acanthias).

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Wood, Chris M; Walsh, Patrick J; Kajimura, Makiko; McClelland, Grant B; Chew, Shit F

2010-04-01

Dogfish sharks are opportunistic predators, eating large meals at irregular intervals. Here we present a synthesis of data from several previous studies on responses in plasma metabolites after natural feeding and during prolonged fasting (up to 56days), together with new data on changes in plasma concentrations of amino acids and non-esterified fatty acids. Post-prandial and long-term fasting responses were compared to control sharks fasted for 7days, a typical inter-meal interval. A feeding frenzy was created in which dogfish were allowed to feed naturally on dead teleosts at two consumed ration levels, 2.6% and 5.5% of body weight. Most responses were more pronounced at the higher ration level. These included increases in urea and TMAO concentrations at 20h, followed by stability through to 56days of fasting. Ammonia levels were low and exhibited little short-term response to feeding, but declined to very low values during the extended fast. Glucose and beta-hydroxybutyrate both fell after feeding, the latter to a greater and more prolonged extent (up to 60h), whereas acetoacetate did not change. During prolonged fasting, glucose concentrations were well regulated, but beta-hydroxybutyrate increased to 2-3-fold control levels. Total plasma amino acid concentrations increased in a biphasic fashion, with peaks at 6-20h, and 48-60h after the meal, followed by homeostasis during the extended fast. Essential and non-essential amino acids generally followed this same pattern, though some exhibited different trends after feeding: taurine, beta-alanine, and glycine (decreases or stability), alanine and glutamine (modest prolonged increases), and threonine, serine, asparagine, and valine (much larger short-term increases). Plasma non-esterified fatty acid concentrations declined markedly through 48h after the 2.6% meal. These data are interpreted in light of companion studies showing elevations in aerobic metabolic rate, urea production, rectal gland function, metabolic

Plasma metabolites associated with type 2 diabetes in a Swedish population: a case-control study nested in a prospective cohort.

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Shi, Lin; Brunius, Carl; Lehtonen, Marko; Auriola, Seppo; Bergdahl, Ingvar A; Rolandsson, Olov; Hanhineva, Kati; Landberg, Rikard

2018-04-01

The aims of the present work were to identify plasma metabolites that predict future type 2 diabetes, to investigate the changes in identified metabolites among individuals who later did or did not develop type 2 diabetes over time, and to assess the extent to which inclusion of predictive metabolites could improve risk prediction. We established a nested case-control study within the Swedish prospective population-based Västerbotten Intervention Programme cohort. Using untargeted liquid chromatography-MS metabolomics, we analysed plasma samples from 503 case-control pairs at baseline (a median time of 7 years prior to diagnosis) and samples from a subset of 187 case-control pairs at 10 years of follow-up. Discriminative metabolites between cases and controls at baseline were optimally selected using a multivariate data analysis pipeline adapted for large-scale metabolomics. Conditional logistic regression was used to assess associations between discriminative metabolites and future type 2 diabetes, adjusting for several known risk factors. Reproducibility of identified metabolites was estimated by intra-class correlation over the 10 year period among the subset of healthy participants; their systematic changes over time in relation to diagnosis among those who developed type 2 diabetes were investigated using mixed models. Risk prediction performance of models made from different predictors was evaluated using area under the receiver operating characteristic curve, discrimination improvement index and net reclassification index. We identified 46 predictive plasma metabolites of type 2 diabetes. Among novel findings, phosphatidylcholines (PCs) containing odd-chain fatty acids (C19:1 and C17:0) and 2-hydroxyethanesulfonate were associated with the likelihood of developing type 2 diabetes; we also confirmed previously identified predictive biomarkers. Identified metabolites strongly correlated with insulin resistance and/or beta cell dysfunction. Of 46 identified

Oral Administration of the Japanese Traditional Medicine Keishibukuryogan-ka-yokuinin Decreases Reactive Oxygen Metabolites in Rat Plasma: Identification of Chemical Constituents Contributing to Antioxidant Activity

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Yosuke Matsubara

2017-02-01

Full Text Available Insufficient detoxification and/or overproduction of reactive oxygen species (ROS induce cellular and tissue damage, and generated reactive oxygen metabolites become exacerbating factors of dermatitis. Keishibukuryogan-ka-yokuinin (KBGY is a traditional Japanese medicine prescribed to treat dermatitis such as acne vulgaris. Our aim was to verify the antioxidant properties of KBGY, and identify its active constituents by blood pharmacokinetic techniques. Chemical constituents were quantified in extracts of KBGY, crude components, and the plasma of rats treated with a single oral administration of KBGY. Twenty-three KBGY compounds were detected in plasma, including gallic acid, prunasin, paeoniflorin, and azelaic acid, which have been reported to be effective for inflammation. KBGY decreased level of the diacron-reactive oxygen metabolites (d-ROMs in plasma. ROS-scavenging and lipid hydroperoxide (LPO generation assays revealed that gallic acid, 3-O-methylgallic acid, (+-catechin, and lariciresinol possess strong antioxidant activities. Gallic acid was active at a similar concentration to the maximum plasma concentration, therefore, our findings indicate that gallic acid is an important active constituent contributing to the antioxidant effects of KBGY. KBGY and its active constituents may improve redox imbalances induced by oxidative stress as an optional treatment for skin diseases.

Routine determination of [18F]-L-6-fluorodopa and its metabolites in blood plasma is essential for accurate positron emission tomography studies

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Chan, G.L.Y.; Hewitt, K.A.; Pate, B.D.; Schofield, P.; Adam, M.J.; Ruth, T.J.

1991-01-01

A batch-contact alumina-extraction method has been used to separate [ 18 F]-L-6-fluorodopa (FD) from its principal metabolite, 3-O-methyl-[ 18 F]-6 fluorodopa (3-OMe-FD), in arterial blood plasma samples collected from subjects pretreated with carbidopa during positron emission tomography (PET) scans. The time course of the metabolite-corrected blood plasma activity is then used as an input function for kinetic analysis of striatal FD uptake. Results obtained from using the batch-contact alumina-extraction method were compared with those from high performance liquid chromatography, and also with those from a chromatographic alumina cartridge technique. In 60 human subjects including normal healthy volunteers and patients diagnoses as having a movement disorder, arterial blood plasma samples were collected after FD injection during a two-hour PET scan and analyzed by the batch-contact alumina-extraction method. The activity ratio (metabolites/FD) increased linearly with time for all subjects. However, there was a wide variation in the slope of the plot of the activity ratio versus time among the subjects. No significant linear or curved relationship was observed between the slope and the age of the subject. Separation of FD from its metabolites is therefore, necessary for each PET-FD study conducted

Urine and plasma metabolites predict the development of diabetic nephropathy in individuals with Type 2 diabetes mellitus

NARCIS (Netherlands)

Pena, M. J.; Lambers Heerspink, H. J.; Hellemons, M. E.; Friedrich, T.; Dallmann, G.; Lajer, M.; Bakker, S. J. L.; Gansevoort, R. T.; Rossing, P.; de Zeeuw, D.; Roscioni, S. S.

Aims Early detection of individuals with Type 2 diabetes mellitus or hypertension at risk for micro- or macroalbuminuria may facilitate prevention and treatment of renal disease. We aimed to discover plasma and urine metabolites that predict the development of micro-or macroalbuminuria. Methods

Rapid solid-phase extraction method to quantify [{sup 11}C]-verapamil, and its [{sup 11}C]-metabolites, in human and macaque plasma

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Unadkat, Jashvant D. [Department of Pharmaceutics, University of Washington, Box 357610, Seattle, WA 98195 (United States)], E-mail: jash@u.washington.edu; Chung, Francisco; Sasongko, Lucy; Whittington, Dale; Eyal, Sara [Department of Pharmaceutics, University of Washington, Box 357610, Seattle, WA 98195 (United States); Mankoff, David [Department of Radiology, University of Washington, Box 356004, Seattle, WA 98195 (United States); Collier, Ann C. [Department of Medicine, University of Washington, Box 359929, Seattle, WA 98195 (United States); Muzi, Mark; Link, Jeanne [Department of Radiology, University of Washington, Box 356004, Seattle, WA 98195 (United States)

2008-11-15

Introduction: P-glycoprotein (P-gp), an efflux transporter, is a significant barrier to drug entry into the brain and the fetus. The positron emission tomography (PET) ligand, [{sup 11}C]-verapamil, has been used to measure in vivo P-gp activity at various tissue-blood barriers of humans and animals. Since verapamil is extensively metabolized in vivo, it is important to quantify the extent of verapamil metabolism in order to interpret such P-gp activity. Therefore, we developed a rapid solid-phase extraction (SPE) method to separate, and then quantify, verapamil and its radiolabeled metabolites in plasma. Methods: Using high-performance liquid chromatography (HPLC), we established that the major identifiable circulating radioactive metabolite of [{sup 11}C]-verapamil in plasma of humans and the nonhuman primate, Macaca nemestrina, was [{sup 11}C]-D-617/717. Using sequential and differential pH elution on C{sub 8} SPE cartridges, we developed a rapid method to separate [{sup 11}C]-verapamil and [{sup 11}C]-D-617/717. Recovery was measured by spiking the samples with the corresponding nonradioactive compounds and assaying these compounds by HPLC. Results: Verapamil and D-617/717 recovery with the SPE method was >85%. When the method was applied to PET studies in humans and nonhuman primates, significant plasma concentration of D-617/717 and unknown polar metabolite(s) were observed. The SPE and the HPLC methods were not significantly different in the quantification of verapamil and D-617/717. Conclusions: The SPE method simultaneously processes multiple samples in less than 5 min. Given the short half-life of [{sup 11}C], this method provides a valuable tool to rapidly determine the concentration of [{sup 11}C]-verapamil and its [{sup 11}C]-metabolites in human and nonhuman primate plasma.

A Protein Extract from Chicken Reduces Plasma Homocysteine in Rats

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Vegard Lysne

2015-06-01

Full Text Available The present study aimed to evaluate effects of a water-soluble protein fraction of chicken (CP, with a low methionine/glycine ratio, on plasma homocysteine and metabolites related to homocysteine metabolism. Male Wistar rats were fed either a control diet with 20% w/w casein as the protein source, or an experimental diet where 6, 14 or 20% w/w of the casein was replaced with the same amount of CP for four weeks. Rats fed CP had reduced plasma total homocysteine level and markedly increased levels of the choline pathway metabolites betaine, dimethylglycine, sarcosine, glycine and serine, as well as the transsulfuration pathway metabolites cystathionine and cysteine. Hepatic mRNA level of enzymes involved in homocysteine remethylation, methionine synthase and betaine-homocysteine S-methyltransferase, were unchanged, whereas cystathionine gamma-lyase of the transsulfuration pathway was increased in the CP treated rats. Plasma concentrations of vitamin B2, folate, cobalamin, and the B-6 catabolite pyridoxic acid were increased in the 20% CP-treated rats. In conclusion, the CP diet was associated with lower plasma homocysteine concentration and higher levels of serine, choline oxidation and transsulfuration metabolites compared to a casein diet. The status of related B-vitamins was also affected by CP.

Determinants of Organophosphorus Pesticide Urinary Metabolite Levels in Young Children Living in an Agricultural Community

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Brenda Eskenazi

2011-04-01

Full Text Available Organophosphorus (OP pesticides are used in agriculture and several are registered for home use. As young children age they may experience different pesticide exposures due to varying diet, behavior, and other factors. We measured six OP dialkylphosphate (DAP metabolites (three dimethyl alkylphosphates (DMAP and three diethyl alkylphosphates (DEAP in urine samples collected from ~400 children living in an agricultural community when they were 6, 12, and 24 months old. We examined bivariate associations between DAP metabolite levels and determinants such as age, diet, season, and parent occupation. To evaluate independent impacts, we then used generalized linear mixed multivariable models including interaction terms with age. The final models indicated that DMAP metabolite levels increased with age. DMAP levels were also positively associated with daily servings of produce at 6- and 24-months. Among the 6-month olds, DMAP metabolite levels were higher when samples were collected during the summer/spring versus the winter/fall months. Among the 12-month olds, DMAP and DEAP metabolites were higher when children lived ≤60 meters from an agricultural field. Among the 24-month-olds, DEAP metabolite levels were higher during the summer/spring months. Our findings suggest that there are multiple determinants of OP pesticide exposures, notably dietary intake and temporal and spatial proximity to agricultural use. The impact of these determinants varied by age and class of DAP metabolite.

Metabolite ratios as potential biomarkers for type 2 diabetes: a DIRECT study

DEFF Research Database (Denmark)

Molnos, Sophie; Wahl, Simone; Haid, Mark

2018-01-01

) and arginine stimulation. We then investigated if the identified metabolite ratios were associated with measures of OGTT-derived beta cell function and with prevalent and incident type 2 diabetes. Methods: We measured the levels of 188 metabolites in plasma samples from 130 healthy members of twin families......Aims/hypothesis: Circulating metabolites have been shown to reflect metabolic changes during the development of type 2 diabetes. In this study we examined the association of metabolite levels and pairwise metabolite ratios with insulin responses after glucose, glucagon-like peptide-1 (GLP-1...... (from the Netherlands Twin Register) at five time points during a modified 3 h hyperglycaemic clamp with glucose, GLP-1 and arginine stimulation. We validated our results in cohorts with OGTT data (n = 340) and epidemiological case–control studies of prevalent (n = 4925) and incident (n = 4277...

Plasma metabolite score correlates with Hypoxia time in a newly born piglet model for asphyxia

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Julia Kuligowski

2017-08-01

Full Text Available Hypoxic-ischemic encephalopathy (HIE secondary to perinatal asphyxia is a leading cause of mortality and acquired long-term neurologic co-morbidities in the neonate. The most successful intervention for the treatment of moderate to severe HIE is moderate whole body hypothermia initiated within 6 h from birth. The objective and prompt identification of infants who are at risk of developing moderate to severe HIE in the critical first hours still remains a challenge. This work proposes a metabolite score calculated based on the relative intensities of three metabolites (choline, 6,8-dihydroxypurine and hypoxanthine that showed maximum correlation with hypoxia time in a consolidated piglet model for neonatal hypoxia-ischemia. The metabolite score's performance as a biomarker for perinatal hypoxia and its usefulness for clinical grading and decision making have been assessed and compared to the performance of lactate which is currently considered the gold standard. For plasma samples withdrawn before and directly after a hypoxic insult, the metabolite score performed similar to lactate. However, it provided an enhanced predictive capacity at 2 h after resuscitation. The present study evidences the usefulness of the metabolite score for improving the early assessment of the severity of the hypoxic insult based on serial determinations in a minimally invasive biofluid. The applicability of the metabolite score for clinical diagnosis and patient stratification for hypothermia treatment has to be confirmed in multicenter trials involving newborns suffering from HIE. Keywords: Hypoxia, Perinatal asphyxia, Newborn, Metabolic biomarker, Neonatal piglet model, Liquid Chromatography – Time-of-Flight Mass Spectrometry (LC-TOF-MS

The concentration of plasma metabolites varies throughout reproduction and affects offspring number in wild brown trout (Salmo trutta).

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Gauthey, Zoé; Freychet, Marine; Manicki, Aurélie; Herman, Alexandre; Lepais, Olivier; Panserat, Stéphane; Elosegi, Arturo; Tentelier, Cédric; Labonne, Jacques

2015-06-01

In wild populations, measuring energy invested in the reproduction and disentangling investment in gametes versus investment in reproductive behavior (such as intrasexual competition or intersexual preference) remain challenging. In this study, we investigated the energy expenditure in brown trout reproductive behavior by using two proxies: variation in weight and variation of plasma metabolites involved in energy production, over the course of reproductive season in a semi natural experimental river. We estimated overall reproductive success using genetic assignment at the end of the reproductive season. Results show that triglycerides and free fatty acid concentrations vary negatively during reproduction, while amino-acids and glucose concentrations remain stable. Decrease in triglyceride and free fatty acid concentrations during reproduction is not related to initial concentration levels or to weight variation. Both metabolite concentration variations and weight variations are correlated to the number of offspring produced, which could indicate that gametic and behavioral reproductive investments substantially contribute to reproductive success in wild brown trout. This study opens a path to further investigate variations in reproductive investment in wild populations. Copyright © 2015 Elsevier Inc. All rights reserved.

Effects of Probiotic Supplementation on Trimethylamine-N-Oxide Plasma Levels in Hemodialysis Patients: a Pilot Study.

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Borges, Natália A; Stenvinkel, P; Bergman, P; Qureshi, A R; Lindholm, B; Moraes, C; Stockler-Pinto, M B; Mafra, D

2018-04-12

Components present in the diet, L-carnitine, choline, and betaine are metabolized by gut microbiota to produce metabolites such as trimethylamine-N-oxide (TMAO) that appear to promote cardiovascular disease in chronic kidney disease (CKD) patients. The objective of this pilot study was to evaluate the effects of probiotic supplementation for 3 months on plasma TMAO levels in CKD patients on hemodialysis (HD). A randomized, double-blind trial was performed in 21 patients [54.8 ± 10.4 years, nine men, BMI 26.1 ± 4.8 kg/m 2 , dialysis vintage 68.5 (34.2-120.7) months]. Ten patients were randomly allocated to the placebo group and 11 to the probiotic group [three capsules, totaling 9 × 10 13 colony-forming units per day of Streptococcus thermophilus (KB19), Lactobacillus acidophilus (KB27), and Bifidobacteria longum (KB31). Plasma TMAO, choline, and betaine levels were measured by LC-MS/MS at baseline and after 3 months. While TMAO did not change after probiotic supplementation, there was a significant increase in betaine plasma levels. In contrast, the placebo group showed a significant decrease in plasma choline levels. Short-term probiotic supplementation does not appear to influence plasma TMAO levels in HD patients. Long-term studies are needed to determine whether probiotics may affect TMAO production in CKD patients.

Effect of metformin on plasma metabolite profile in the Copenhagen Insulin and Metformin Therapy (CIMT) trial

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Safai, N; Suvitaival, T; A, Ali

2018-01-01

of the Copenhagen Insulin and Metformin Therapy (CMIT) trial, a multicentre study from May 2008 to December 2012, was carried out. We used a non-target method to analyse 87 plasma metabolites in participants with Type 2 diabetes (n = 370) who were randomized in a 1 : 1 ratio to 18 months of metformin or placebo...

Measurement of caffeine and its three primary metabolites in human plasma by HPLC-ESI-MS/MS and clinical application.

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Chen, Feng; Hu, Zhe-Yi; Parker, Robert B; Laizure, S Casey

2017-06-01

Caffeine is a mild stimulant with significant potential for abuse, being consumed in larger doses with the widespread availability of energy drinks and by novel routes of administration such as inspired powder, oral sprays and electronic cigarettes. How these recent changes in caffeine consumption affecting caffeine disposition and abuse potential is of growing concern. In the study of caffeine disposition in humans, it is common to only measure the caffeine concentration; however, caffeine's three major metabolites (paraxanthine, theobromine and theophylline) retain central nervous system stimulant activity that may contribute to the overall pharmacological activity and toxicity. Therefore, it would be scientifically more rigorous to measure caffeine and its major metabolites in the evaluation of caffeine disposition in human subjects. Herein, we report a method for the simultaneous quantification of caffeine and its three major metabolites in human plasma by high-performance liquid chromatography coupled to electrospray tandem mass spectrometry (HPLC-ESI-MS/MS). Human plasma samples were treated by simple protein precipitation and the analytes were separated using a 6 min gradient program. Precision and accuracy were well within in the 15% acceptance range. The simple sample preparation, short runtime, sensitivity and the inclusion of caffeine's major metabolites make this assay methodology optimal for the study of caffeine's pharmacokinetics and pharmacodynamics in human subjects. Copyright © 2016 John Wiley & Sons, Ltd.

Tissue distribution of berberine and its metabolites after oral administration in rats.

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Xiang-Shan Tan

Full Text Available Berberine (BBR has been confirmed to have multiple bioactivities in clinic, such as cholesterol-lowering, anti-diabetes, cardiovascular protection and anti- inflammation. However, BBR's plasma level is very low; it cannot explain its pharmacological effects in patients. We consider that the in vivo distribution of BBR as well as of its bioactive metabolites might provide part of the explanation for this question. In this study, liquid chromatography coupled to ion trap time-of-flight mass spectrometry (LC/MS(n-IT-TOF as well as liquid chromatography that coupled with tandem mass spectrometry (LC-MS/MS was used for the study of tissue distribution and pharmacokinetics of BBR in rats after oral administration (200 mg/kg. The results indicated that BBR was quickly distributed in the liver, kidneys, muscle, lungs, brain, heart, pancreas and fat in a descending order of its amount. The pharmacokinetic profile indicated that BBR's level in most of studied tissues was higher (or much higher than that in plasma 4 h after administration. BBR remained relatively stable in the tissues like liver, heart, brain, muscle, pancreas etc. Organ distribution of BBR's metabolites was also investigated paralleled with that of BBR. Thalifendine (M1, berberrubine (M2 and jatrorrhizine (M4, which the metabolites with moderate bioactivity, were easily detected in organs like the liver and kidney. For instance, M1, M2 and M4 were the major metabolites in the liver, among which the percentage of M2 was up to 65.1%; the level of AUC (0-t (area under the concentration-time curve for BBR or the metabolites in the liver was 10-fold or 30-fold higher than that in plasma, respectively. In summary, the organ concentration of BBR (as well as its bioactive metabolites was higher than its concentration in the blood after oral administration. It might explain BBR's pharmacological effects on human diseases in clinic.

Estrogenic activities of diuron metabolites in female Nile tilapia (Oreochromis niloticus).

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Pereira, Thiago Scremin Boscolo; Boscolo, Camila Nomura Pereira; Felício, Andreia Arantes; Batlouni, Sergio Ricardo; Schlenk, Daniel; de Almeida, Eduardo Alves

2016-03-01

Some endocrine disrupting chemicals (EDCs) can alter the estrogenic activities of the organism by directly interacting with estrogen receptors (ER) or indirectly through the hypothalamus-pituitary-gonadal axis. Recent studies in male Nile tilapia (Oreochromis niloticus) indicated that diuron may have anti-androgenic activity augmented by biotransformation. In this study, the effects of diuron and three of its metabolites were evaluated in female tilapia. Sexually mature female fish were exposed for 25 days to diuron, as well as to its metabolites 3,4-dichloroaniline (DCA), 3,4-dichlorophenylurea (DCPU) and 3,4-dichlorophenyl-N-methylurea (DCPMU), at concentrations of 100 ng/L. Diuron metabolites caused increases in E2 plasma levels, gonadosomatic indices and in the percentage of final vitellogenic oocytes. Moreover, diuron and its metabolites caused a decrease in germinative cells. Significant differences in plasma concentrations of the estrogen precursor and gonadal regulator17α-hydroxyprogesterone (17α-OHP) were not observed. These results show that diuron metabolites had estrogenic effects potentially mediated through enhanced estradiol biosynthesis and accelerated the ovarian development of O. niloticus females. Copyright © 2015 Elsevier Ltd. All rights reserved.

Effects of aripiprazole and the Taq1A polymorphism in the dopamine D2 receptor gene on the clinical response and plasma monoamine metabolites level during the acute phase of schizophrenia.

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Miura, Itaru; Takeuchi, Satoshi; Katsumi, Akihiko; Mori, Azuma; Kanno, Keiko; Yang, Qiaohui; Mashiko, Hirobumi; Numata, Yoshihiko; Niwa, Shin-Ichi

2012-02-01

The Taq1A polymorphism in the dopamine D2 receptor (DRD2) gene could be related to the response to antipsychotics. We examined the effects of the Taq1A polymorphism on the plasma monoamine metabolites during the treatment of schizophrenia with aripiprazole, a DRD2 partial agonist. Thirty Japanese patients with schizophrenia were treated with aripiprazole for 6 weeks. We measured plasma levels of homovanillic acid (pHVA) and 3-methoxy-4hydroxyphenylglycol (pMHPG) before and after treatment. The Taq1A polymorphism was genotyped with polymerase chain reaction. Aripiprazole improved the acute symptoms of schizophrenia and decreased pHVA in responders (P = 0.023) but not in nonresponders (P = 0.28). Although A1 allele carriers showed a tendency to respond to aripiprazole (61.5%) compared to A1 allele noncarriers (29.4%) (P = 0.078), there was not statistically significant difference in the response between the 2 genotype groups. There were significant effect for response (P = 0.013) and genotype × response interaction (P = 0.043) on the change of pHVA. The changes of pHVA differ between responders and nonresponders in A1 allele carriers but not in A1 allele noncarriers. There were no genotype or response effects or genotype × response interaction on the changes of the plasma levels of 3-methoxy-4hydroxyphenylglycol. Our preliminary results suggest that Taq1A polymorphism may be partly associated with changes in pHVA during acute schizophrenia.

Profile of plasma and urine metabolites after the intake of almond [Prunus dulcis (Mill.) D.A. Webb] polyphenols in humans.

Science.gov (United States)

Urpi-Sarda, Mireia; Garrido, Ignacio; Monagas, María; Gómez-Cordovés, Carmen; Medina-Remón, Alexander; Andres-Lacueva, Cristina; Bartolomé, Begoña

2009-11-11

Nut skins are considered to be a rich source of polyphenols and may be partially responsible for the numerous health effects associated with nut consumption. However, more bioavailability studies of nut skin polyphenols are needed to understand the health effects derived from nut consumption. The aim of the present study was to determine the profiles of both phase II and microbial-derived phenolic metabolites in plasma and urine samples before and after the intake of almond skin polyphenols by healthy human subjects (n = 2). Glucuronide, O-methyl glucuronide, sulfate, and O-methyl sulfate derivatives of (epi)catechin, as well as the glucuronide conjugates of naringenin and glucuronide and sulfate conjugates of isorhamnetin, were detected in plasma and urine samples after consumption of almond skin polyphenols. The main microbial-derived metabolites of flavanols, such as 5-(dihydroxyphenyl)-gamma-valerolactone and 5-(hydroxymethoxyphenyl)-gamma-valerolactone, were also detected in their glucuronide and sulfate forms. In addition, numerous metabolites derived from further microbial degradation of hydroxyphenylvalerolactones, including hydroxyphenylpropionic, hydroxyphenylacetic, hydroxycinnamic, hydroxybenzoic, and hydroxyhippuric acids, registered major changes in urine after the consumption of almond skin polyphenols. The urinary excretion of these microbial metabolites was estimated to account for a larger proportion of the total polyphenol ingested than phase II metabolites of (epi)catechin, indicating the important role of intestinal bacteria in the metabolism of highly polymerized almond skin polyphenols. To the authors' knowledge this study constitutes the most complete report of the absorption of almond skin polyphenols in humans.

Identification of an Epoxide Metabolite of Lycopene in Human Plasma Using 13C-Labeling and QTOF-MS.

Science.gov (United States)

Cichon, Morgan J; Moran, Nancy E; Riedl, Ken M; Schwartz, Steven J; Clinton, Steven K

2018-03-20

The carotenoid lycopene is a bioactive component of tomatoes and is hypothesized to reduce risk of several chronic diseases, such as prostate cancer. The metabolism of lycopene is only beginning to be understood and some studies suggest that metabolites of lycopene may be partially responsible for bioactivity associated with the parent compound. The detection and characterization of these compounds in vivo is an important step in understanding lycopene bioactivity. The metabolism of lycopene likely involves both chemical and enzymatic oxidation. While numerous lycopene metabolites have been proposed, few have actually been identified in vivo following lycopene intake. Here, LC-QTOF-MS was used along with 13 C-labeling to investigate the post-prandial oxidative metabolism of lycopene in human plasma. Previously reported aldehyde cleavage products were not detected, but a lycopene 1,2-epoxide was identified as a new candidate oxidative metabolite.

Plasma and serum lipidomics of healthy white adults shows characteristic profiles by subjects' gender and age.

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Masaki Ishikawa

Full Text Available Blood is a commonly used biofluid for biomarker discovery. Although blood lipid metabolites are considered to be potential biomarker candidates, their fundamental properties are not well characterized. We aimed to (1 investigate the matrix type (serum vs. plasma that may be preferable for lipid biomarker exploration, (2 elucidate age- and gender-associated differences in lipid metabolite levels, and (3 examine the stability of lipid metabolites in matrix samples subjected to repeated freeze-thaw cycles. Using liquid chromatography-mass spectrometry, we performed lipidomic analyses for fasting plasma and serum samples for four groups (15 subjects/group of young and elderly (25-34 and 55-64 years old, respectively males and females and for an additional aliquot of samples from young males, which were subjected to repeated freeze-thaw cycles. Lysophosphatidylcholine and diacylglycerol levels were higher in serum than in plasma samples, suggesting that the clotting process influences serum lipid metabolite levels. Gender-associated differences highlighted that the levels of many sphingomyelin species were significantly higher in females than in males, irrespective of age and matrix (plasma and serum. Age-associated differences were more prominent in females than in males, and in both matrices, levels of many triacylglycerols were significantly higher in elderly females than in young females. Plasma and serum levels of most lipid metabolites were reduced by freeze-thawing. Our results indicate that plasma is an optimal matrix for exploring lipid biomarkers because it represents the original properties of an individual's blood sample. In addition, the levels of some blood lipid species of healthy adults showed gender- and age-associated differences; thus, this should be considered during biomarker exploration and its application in diagnostics. Our fundamental findings on sample selection and handling procedures for measuring blood lipid metabolites

Identification of known chemicals and their metabolites from Alpinia oxyphylla fruit extract in rat plasma using liquid chromatography/tandem mass spectrometry (LC-MS/MS) with selected reaction monitoring.

Science.gov (United States)

Chen, Feng; Li, Hai-Long; Tan, Yin-Feng; Li, Yong-Hui; Lai, Wei-Yong; Guan, Wei-Wei; Zhang, Jun-Qing; Zhao, Yuan-Sheng; Qin, Zhen-Miao

2014-08-01

Alpinia oxyphylla (Yizhi) capsularfruits are commonly used in traditional medicine. Pharmacological studies have demonstrated that A. oxyphylla capsularfruits have some beneficial roles. Besides volatile oil, sesquiterpenes, diarylheptanoids and flavonoids are main bioactive constituents occurring in the Yizhi capsularfruits. The representative constituents include tectochrysin, izalpinin, chrysin, apigenin-4',7-dimethylether, kaempferide, yakuchinone A, yakuchinone B, oxyphyllacinol and nootkatone. Their content levels in the fruit and its pharmaceutical preparations have been reported by our group. The nine phytochemicals are also the major components present in the Yizhi alcoholic extracts, which have anti-diarrheal activities. However, the fates of these constituents in the body after oral or intravenous administration remain largely unknown. In the present study, we focus on these phytochemicals albeit other concomitant compounds. The chemicals and their metabolites in rat plasma were identified using liquid chromatography/tandem mass spectrometry with selected reaction monitoring mode after orally administered Yizhi extract to rats. Rat plasma samples were treated by methanol precipitation, acidic or enzymatic hydrolysis. This target analysis study revealed that: (1) low or trace plasma levels of parent chemicals were measured after p.o. administration of Yizhi extract, Suoquan capsules and pills to rats; (2) flavonoids and diarylheptanoids formed mainly monoglucuronide metabolites; however, diglucuronide metabolites for chrysin, izalpinin and kaempferide were also detected; (3) metabolic reduction of Yizhi diarylheptanoids occurred in rats. Yakuchinone B was reduced to yakuchinone A and then to oxyphyllacinol in a stepwise manner and subsequently glucuronidated by UDP-glucuronosyl transferase. Further research is needed to characterize the UDP-glucuronosyl transferase and reductase involved in the biotransformation of Yizhi chemicals. Copyright © 2014

Relationship between discriminative stimulus effects and plasma methamphetamine and amphetamine levels of intramuscular methamphetamine in male rhesus monkeys

OpenAIRE

Banks, Matthew L.; Smith, Douglas A.; Kisor, David F.; Poklis, Justin L.

2015-01-01

Methamphetamine is a globally abused drug that is metabolized to amphetamine, which also produces abuse-related behavioral effects. However, the contributing role of methamphetamine metabolism to amphetamine in methamphetamine's abuse-related subjective effects is unknown. This preclinical study was designed to determine 1) the relationship between plasma methamphetamine levels and methamphetamine discriminative stimulus effects and 2) the contribution of the methamphetamine metabolite amphet...

Simultaneous quantification of caffeine and its three primary metabolites in rat plasma by liquid chromatography-tandem mass spectrometry.

Science.gov (United States)

Choi, Eu Jin; Bae, Soo Hyeon; Park, Jung Bae; Kwon, Min Jo; Jang, Su Min; Zheng, Yu Fen; Lee, Young Sun; Lee, Su-Jun; Bae, Soo Kyung

2013-12-01

A rapid, sensitive, simple and accurate LC-MS/MS method for the simultaneous quantitation of caffeine, and its three primary metabolites, theobromine, paraxanthine, and theophylline, in rat plasma was developed and validated. Chromatographic separation was performed on an Agilent Poroshell 120 EC-C18 column using 1 μg/mL acetaminophen as an internal standard. Each sample was run at 0.5 mL/min for a total run time of 7 min/sample. Detection and quantification were performed using a mass spectrometer in selected reaction-monitoring mode with positive electrospray ionization. The lower limit of quantification was 5 ng/mL for all analytes with linear ranges up to 5000 ng/mL for caffeine and 1000 ng/mL for its metabolites. The coefficient of variation for assay precision was less than 12.6%, with an accuracy of 93.5-114%. The assay was successfully applied to determine plasma concentrations of caffeine, theobromine, paraxanthine, and theophylline in rat administered various energy drinks containing the same caffeine content. Various energy drinks exhibited considerable variability in the pharmacokinetic profiles of caffeine and its three primary metabolites, even containing the same caffeine. Different additives of energy drinks might contribute to these results. Copyright © 2013 Elsevier Ltd. All rights reserved.

Metabolites of alectinib in human: their identification and pharmacological activity

Directory of Open Access Journals (Sweden)

Mika Sato-Nakai

2017-07-01

Full Text Available Two metabolites (M4 and M1b in plasma and four metabolites (M4, M6, M1a and M1b in faeces were detected through the human ADME study following a single oral administration of [14C]alectinib, a small-molecule anaplastic lymphoma kinase inhibitor, to healthy subjects. In the present study, M1a and M1b, which chemical structures had not been identified prior to the human ADME study, were identified as isomers of a carboxylate metabolite oxidatively cleaved at the morpholine ring. In faeces, M4 and M1b were the main metabolites, which shows that the biotransformation to M4 and M1b represents two main metabolic pathways for alectinib. In plasma, M4 was a major metabolite and M1b was a minor metabolite. The contribution to in vivo pharmacological activity of these circulating metabolites was assessed from their in vitro pharmacological activity and plasma protein binding. M4 had a similar cancer cell growth inhibitory activity and plasma protein binding to that of alectinib, suggesting its contribution to the antitumor activity of alectinib, whereas the pharmacological activity of M1b was insignificant.

A validated HPLC-MS/MS assay for quantifying unstable pharmacologically active metabolites of clopidogrel in human plasma: application to a clinical pharmacokinetic study.

Science.gov (United States)

Furlong, Michael T; Savant, Ishani; Yuan, Moucun; Scott, Laura; Mylott, William; Mariannino, Thomas; Kadiyala, Pathanjali; Roongta, Vikram; Arnold, Mark E

2013-05-01

Clopidogrel is prescribed for the treatment of Acute Coronary Syndrome and recent myocardial infarction, recent stroke, or established peripheral arterial disease. A sensitive and reliable high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) assay was developed and validated to enable reliable quantification of four diastereomeric and chemically reactive thiol metabolites, two of which are pharmacologically active, in human plasma. The metabolites were stabilized by alkylation of their reactive thiol moieties with 2-bromo-3'-methoxyacetophenone (MPB). Following organic solvent mediated-protein precipitation in a 96-well plate format, chromatographic separation was achieved by gradient elution on an Ascentis Express RP-amide column. Chromatographic conditions were optimized to ensure separation of the four derivatized active metabolites. Derivatized metabolites and stable isotope-labeled internal standards were detected by positive ion electrospray tandem mass spectrometry. The HPLC-MS/MS assay was validated over concentration ranges of 0.125-125 ng/mL for metabolites H1-H3 and 0.101-101 ng/mL for H4. Intra- and inter-assay precision values for replicate quality control samples were within 14.3% for all analytes during the assay validation. Mean quality control accuracy values were within ±6.3% of nominal values for all analytes. Assay recoveries were high (>79%). The four derivatized analytes were stable in human blood for at least 2 h at room temperature and on ice. The analytes were also stable in human plasma for at least 25 h at room temperature, 372 days at -20 °C and -70 °C, and following at least five freeze-thaw cycles. The validated assay was successfully applied to the quantification of all four thiol metabolites in human plasma in support of a human pharmacokinetic study. Copyright © 2013 Elsevier B.V. All rights reserved.

Radiochemical plasma salicylamide assay using ring-labeled tritiated salicylamide

Energy Technology Data Exchange (ETDEWEB)

Stella, V J; Varia, S A; Riedy, M

1979-05-01

A rat plasma salicylamide assay was developed using ring-labeled tritiated salicylamide, synthesized by reacting salicylamide with tritium oxide in the presence of heptafluorobutyric acid. The reaction yielded /sup 3/H-salicylamide of specific activity up to 8.41 mCi/mmole, 60% yield. Plasma containing /sup 3/H-salicylamide and its metabolites was extracted with a toluene-based scintillation fluid, which was subsequently counted. Specificity for free salicylamide was demonstrated by radiochemical and standard fluorescence plasma salicylamide level-time curves. Specificity resulted from nonextraction of the salicylamide sulfate and glucuronide metabolites. Sulfatase and beta-glucuronidase treatment allowed the analysis of plasma sulfate and glucuronide conjugates as free salicylamide. This procedure should be effective for the analysis of salicylamide and its metabolites in the presence of similar phenolic compounds.

Identification of an Epoxide Metabolite of Lycopene in Human Plasma Using 13C-Labeling and QTOF-MS

Directory of Open Access Journals (Sweden)

Morgan J. Cichon

2018-03-01

Full Text Available The carotenoid lycopene is a bioactive component of tomatoes and is hypothesized to reduce risk of several chronic diseases, such as prostate cancer. The metabolism of lycopene is only beginning to be understood and some studies suggest that metabolites of lycopene may be partially responsible for bioactivity associated with the parent compound. The detection and characterization of these compounds in vivo is an important step in understanding lycopene bioactivity. The metabolism of lycopene likely involves both chemical and enzymatic oxidation. While numerous lycopene metabolites have been proposed, few have actually been identified in vivo following lycopene intake. Here, LC-QTOF-MS was used along with 13C-labeling to investigate the post-prandial oxidative metabolism of lycopene in human plasma. Previously reported aldehyde cleavage products were not detected, but a lycopene 1,2-epoxide was identified as a new candidate oxidative metabolite.

Increased plasma concentrations of vasopressin, oxytocin, cortisol and the prostaglandin F2alpha metabolite during labour in the dog.

Science.gov (United States)

Olsson, K; Bergström, A; Kindahl, H; Lagerstedt, A-S

2003-11-01

This study investigated if the plasma vasopressin concentration increases during labour in the dog and whether the change in vasopressin correlates with that of oxytocin, 15-ketodihydro-PGF2alpha and cortisol. Five beagle dogs each delivered three to seven puppies. Blood samples were taken from a catheter inserted into the cephalic vein during labour and by venepuncture during the other periods. Vasopressin concentration increased from 2 +/- 0 pmol L-1 (anoestrus) to 26 +/- 11 pmol L-1 at the birth of the first puppy, remained high at the birth of the second puppy and then decreased. Oxytocin increased from 63 +/- 5 pmol L-1 (anoestrus) to 166 +/- 19 pmol L-1 at the birth of the first puppy and remained elevated throughout labour. The PGF2alpha metabolite concentration increased from 0.2 +/- 0.0 nmol L-1 (anoestrus) to 66 +/- 17 nmol L-1 at the birth of the first puppy and remained elevated 1 h after the completion of parturition. The cortisol concentration increased from 49 +/- 9 nmol L-1 (anoestrus) to 242 +/- 35 nmol L-1 at the birth of the first puppy, remained high during the birth of the second puppy and then declined. The plasma level of vasopressin was strongly correlated with that of cortisol but less with that of the PGF2alpha metabolite, and not significantly with the concentration of oxytocin. This indicates that the four hormones play different roles during labour in the dog.

Gut Microbiota-Regulated Pharmacokinetics of Berberine and Active Metabolites in Beagle Dogs After Oral Administration.

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Feng, Ru; Zhao, Zhen-Xiong; Ma, Shu-Rong; Guo, Fang; Wang, Yan; Jiang, Jian-Dong

2018-01-01

Berberine (BBR) is considered a multi-target drug that has significant advantages. In contrast to its significant pharmacological effects in clinic, the plasma level of BBR is very low. Our previous work revealed that dihydroberberine (dhBBR) could be an absorbable form of BBR in the intestine, and butyrate is an active metabolite that is generated by gut bacteria in rats. In this study, for the first time we describe gut microbiota-regulated pharmacokinetics in beagle dogs after oral administration of BBR by single (50 mg/kg) or multiple doses (50 mg/kg/d) for 7 days. GC-MS, GC, LC-MS/MS, and LC/MS n -IT-TOF were used to detect dhBBR, butyrate and BBR as well as its Phase I and II metabolites, respectively. The results showed that dhBBR was not detected in dog plasma but was excreted in small amounts in the feces of dogs examined on days 3 and 7. Butyrate was generated by gut bacteria and increased by 1.3- and 1.2-fold in plasma or feces, respectively, after 7 days of BBR treatment compared to the levels before treatment. Changes of intestinal bacterial composition were analyzed by 16S rRNA genes analysis. The results presented that dogs treated with BBR for 7 days increased both the abundance of the butyrate- and the nitroreductases- producing bacteria. We also identified chemical structures of the Phase I and II metabolites and analyzed their contents in beagle dogs. Eleven metabolites were detected in plasma and feces after BBR oral administration (50 mg/kg) to dogs, including 8 metabolites of Phase I and III metabolites of Phase II. The pharmacokinetic profile indicated that the concentration of BBR in plasma was low, with a C max value of 36.88 ± 23.45 ng/mL. The relative content of glucuronic acid conjugates (M11) was higher than those of other metabolites (M1, M2, M12, and M14) in plasma. BBR was detected in feces, with high excreted amounts on day 3 (2625.04 ± 1726.94 μg/g) and day 7 (2793.43 ± 488.10 μg/g). In summary, this is the first study to

Ameliorating effects of Mango (Mangifera indica L.) fruit on plasma ethanol level in a mouse model assessed with 1H-NMR based metabolic profiling

Science.gov (United States)

Kim, So-Hyun; K. Cho, Somi; Min, Tae-Sun; Kim, Yujin; Yang, Seung-Ok; Kim, Hee-Su; Hyun, Sun-Hee; Kim, Hana; Kim, Young-Suk; Choi, Hyung-Kyoon

2011-01-01

The ameliorating effects of Mango (Mangifera indica L.) flesh and peel samples on plasma ethanol level were investigated using a mouse model. Mango fruit samples remarkably decreased mouse plasma ethanol levels and increased the activities of alcohol dehydrogenase and acetaldehyde dehydrogenase. The 1H-NMR-based metabolomic technique was employed to investigate the differences in metabolic profiles of mango fruits, and mouse plasma samples fed with mango fruit samples. The partial least squares-discriminate analysis of 1H-NMR spectral data of mouse plasma demonstrated that there were clear separations among plasma samples from mice fed with buffer, mango flesh and peel. A loading plot demonstrated that metabolites from mango fruit, such as fructose and aspartate, might stimulate alcohol degradation enzymes. This study suggests that mango flesh and peel could be used as resources for functional foods intended to decrease plasma ethanol level after ethanol uptake. PMID:21562641

Simultaneous measurement of plasma levels of imipramine and desipramine in patients with primary affective disorders

International Nuclear Information System (INIS)

Claeys, M.; Muscettola, G.; Goodwin, F.K.; Markey, S.P.

1975-01-01

A GC-MS method has been applied for the quantitative determination of nanogram levels of imipramine and its N-demethylated metabolite, desipramine, in plasma samples. The method involves a mild trifluoroacetylating method, using trifluoroacetylimidazole as derivatizing reagent. Specific detection is performed by selected ion recording of the [MH] + ions, formed upon chemical ionization with methane as reagent gas. Quantitative analysis is achieved by stable isotope dilution techniques, using 2 H-labeled analogs as internal standards. Results on patient samples are included

Identification of 4-hydroxyheptachlorostyrene in polar bear plasma and its binding affinity to transhyretin: a metabolite of octachlorostyrene

NARCIS (Netherlands)

Sandau, C.D.; Meerts, I.A.T.M.; Letcher, R.J.; McAlee, A.J.; Chittim, B.; Brouwer, A.; Norstrom, R.J.

2000-01-01

A new compound, 4-hydroxyheptachlorostyrene (4-OH-HpCS), was identified as a major component in the chlorinated phenolic compound fraction of polar bear plasma. The structure was hypothesized to be 4-OH-HpCS based on mass spectral interpretation, the assumption that it was a metabolite of

Identification of 4-hydroxyheptachlorostyrene in polar bear plasma and its binding affinity to transthyretin : a metabolite of octachlorostyrene?

NARCIS (Netherlands)

Standau, C.D.; Meerts, I.A.T.M.; Letcher, R.J.; McAlees, A.J.; Chittim, B.; Brouwer, A.; Norstrom, R.J.

2000-01-01

A new compound, 4-hydroxyheptachlorostyrene (4-OH-HpCS), was identified as a major component in the chlorinated phenolic compound fraction of polar bear plasma. The structure was hypothesized to be 4-OH-HpCS based on mass spectral interpretation, the assumption that it was a metabolite of

Race and sex differences in small-molecule metabolites and metabolic hormones in overweight and obese adults.

Science.gov (United States)

Patel, Mahesh J; Batch, Bryan C; Svetkey, Laura P; Bain, James R; Turer, Christy Boling; Haynes, Carol; Muehlbauer, Michael J; Stevens, Robert D; Newgard, Christopher B; Shah, Svati H

2013-12-01

In overweight/obese individuals, cardiometabolic risk factors differ by race and sex categories. Small-molecule metabolites and metabolic hormone levels might also differ across these categories and contribute to risk factor heterogeneity. To explore this possibility, we performed a cross-sectional analysis of fasting plasma levels of 69 small-molecule metabolites and 13 metabolic hormones in 500 overweight/obese adults who participated in the Weight Loss Maintenance trial. Principal-components analysis (PCA) was used for reduction of metabolite data. Race and sex-stratified comparisons of metabolite factors and metabolic hormones were performed. African Americans represented 37.4% of the study participants, and females 63.0%. Of thirteen metabolite factors identified, three differed by race and sex: levels of factor 3 (branched-chain amino acids and related metabolites, phormones regulating body weight homeostasis. Among overweight/obese adults, there are significant race and sex differences in small-molecule metabolites and metabolic hormones; these differences may contribute to risk factor heterogeneity across race and sex subgroups and should be considered in future investigations with circulating metabolites and metabolic hormones.

Ultra high performance liquid chromatography-quadrupole-time of flight analysis for the identification and the determination of resveratrol and its metabolites in mouse plasma

International Nuclear Information System (INIS)

Menet, M.C.; Cottart, C.H.; Taghi, M.; Nivet-Antoine, V.; Dargère, D.

2013-01-01

Graphical abstract: Simultaneous identification and determination of new resveratrol metabolites in mice by UHPLC-Q-TOF in full scan mode. Highlights: ► Fast method to quantify resveratrol and its main metabolites in the mouse plasma. ► Isotope-labeled standards to build a linear calibration curve. ► Linear calibration curve on a wide range of concentrations. ► Simultaneous identification and quantification of metabolites by using full scan mode. ► Detection of uncommon metabolites not yet described in mice. - Abstract: Resveratrol is a polyphenol that has numerous interesting biological properties, but, per os, it is quickly metabolized. Some of its metabolites are more concentrated than resveratrol, may have greater biological activities, and may act as a kind of store for resveratrol. Thus, to understand the biological impact of resveratrol on a physiological system, it is crucial to simultaneously analyze resveratrol and its metabolites in plasma. This study presents an analytical method based on UHPLC-Q-TOF mass spectrometry for the quantification of resveratrol and of its most common hydrophilic metabolites. The use of 13 C- and D-labeled standards specific to each molecule led to a linear calibration curve on a larger concentration range than described previously. The use of high resolution mass spectrometry in the full scan mode enabled simultaneous identification and quantification of some hydrophilic metabolites not previously described in mice. In addition, UHPLC separation, allowing run times lower than 10 min, can be used in studies that requiring analysis of many samples.

Ultra high performance liquid chromatography-quadrupole-time of flight analysis for the identification and the determination of resveratrol and its metabolites in mouse plasma

Energy Technology Data Exchange (ETDEWEB)

Menet, M.C., E-mail: marie-claude.menet@parisdescartes.fr [Universite Paris Descartes, Sorbonne Paris cite, EA 4463, Faculte des Sciences Pharmaceutiques et Biologiques, 4 avenue de l' Observatoire, Paris 75270 (France); Cottart, C.H. [APHP, Groupe hospitalier Pitie-Salpetriere, Charles Foix, Service de Biochimie, 7 avenue de la Republique, Ivry sur Seine 94205 (France); Universite Paris Descartes, Sorbonne Paris cite, EA 4466, Faculte des Sciences Pharmaceutiques et Biologiques, 4 avenue de l' Observatoire, Paris 75270 (France); Taghi, M. [Universite Paris Descartes, Sorbonne Paris cite, EA 4463, Faculte des Sciences Pharmaceutiques et Biologiques, 4 avenue de l' Observatoire, Paris 75270 (France); Nivet-Antoine, V. [Universite Paris Descartes, Sorbonne Paris cite, EA 4466, Faculte des Sciences Pharmaceutiques et Biologiques, 4 avenue de l' Observatoire, Paris 75270 (France); APHP, Hopital Europeen Georges Pompidou, Service de Biochimie, 20 rue Leblanc, Paris 75015 (France); Dargere, D. [Universite Paris Descartes, Sorbonne Paris cite, EA 4463, Faculte des Sciences Pharmaceutiques et Biologiques, 4 avenue de l' Observatoire, Paris 75270 (France); and others

2013-01-25

Graphical abstract: Simultaneous identification and determination of new resveratrol metabolites in mice by UHPLC-Q-TOF in full scan mode. Highlights: Black-Right-Pointing-Pointer Fast method to quantify resveratrol and its main metabolites in the mouse plasma. Black-Right-Pointing-Pointer Isotope-labeled standards to build a linear calibration curve. Black-Right-Pointing-Pointer Linear calibration curve on a wide range of concentrations. Black-Right-Pointing-Pointer Simultaneous identification and quantification of metabolites by using full scan mode. Black-Right-Pointing-Pointer Detection of uncommon metabolites not yet described in mice. - Abstract: Resveratrol is a polyphenol that has numerous interesting biological properties, but, per os, it is quickly metabolized. Some of its metabolites are more concentrated than resveratrol, may have greater biological activities, and may act as a kind of store for resveratrol. Thus, to understand the biological impact of resveratrol on a physiological system, it is crucial to simultaneously analyze resveratrol and its metabolites in plasma. This study presents an analytical method based on UHPLC-Q-TOF mass spectrometry for the quantification of resveratrol and of its most common hydrophilic metabolites. The use of {sup 13}C- and D-labeled standards specific to each molecule led to a linear calibration curve on a larger concentration range than described previously. The use of high resolution mass spectrometry in the full scan mode enabled simultaneous identification and quantification of some hydrophilic metabolites not previously described in mice. In addition, UHPLC separation, allowing run times lower than 10 min, can be used in studies that requiring analysis of many samples.

Plasma biomarker of dietary phytosterol intake.

Science.gov (United States)

Lin, Xiaobo; Racette, Susan B; Ma, Lina; Wallendorf, Michael; Spearie, Catherine Anderson; Ostlund, Richard E

2015-01-01

Dietary phytosterols, plant sterols structurally similar to cholesterol, reduce intestinal cholesterol absorption and have many other potentially beneficial biological effects in humans. Due to limited information on phytosterol levels in foods, however, it is difficult to quantify habitual dietary phytosterol intake (DPI). Therefore, we sought to identify a plasma biomarker of DPI. Data were analyzed from two feeding studies with a total of 38 subjects during 94 dietary periods. DPI was carefully controlled at low, intermediate, and high levels. Plasma levels of phytosterols and cholesterol metabolites were assessed at the end of each diet period. Based on simple ordinary least squares regression analysis, the best biomarker for DPI was the ratio of plasma campesterol to the endogenous cholesterol metabolite 5-α-cholestanol (R2 = 0.785, P 0.600; P phytosterol intake. Conversely, plasma phytosterol levels alone are not ideal biomarkers of DPI because they are confounded by large inter-individual variation in absorption and turnover of non-cholesterol sterols. Further work is needed to assess the relation between non-cholesterol sterol metabolism and associated cholesterol transport in the genesis of coronary heart disease.

A diet rich in high-glucoraphanin broccoli interacts with genotype to reduce discordance in plasma metabolite profiles by modulating mitochondrial function123

Science.gov (United States)

Armah, Charlotte N; Traka, Maria H; Dainty, Jack R; Defernez, Marianne; Janssens, Astrid; Leung, Wing; Doleman, Joanne F; Potter, John F

2013-01-01

Background: Observational and experimental studies suggest that diets rich in cruciferous vegetables and glucosinolates may reduce the risk of cancer and cardiovascular disease (CVD). Objective: We tested the hypothesis that a 12-wk dietary intervention with high-glucoraphanin (HG) broccoli would modify biomarkers of CVD risk and plasma metabolite profiles to a greater extent than interventions with standard broccoli or peas. Design: Subjects were randomly assigned to consume 400 g standard broccoli, 400 g HG broccoli, or 400 g peas each week for 12 wk, with no other dietary restrictions. Biomarkers of CVD risk and 347 plasma metabolites were quantified before and after the intervention. Results: No significant differences in the effects of the diets on biomarkers of CVD risk were found. Multivariate analyses of plasma metabolites identified 2 discrete phenotypic responses to diet in individuals within the HG broccoli arm, differentiated by single nucleotide polymorphisms associated with the PAPOLG gene. Univariate analysis showed effects of sex (P broccoli arm, the consequence of the intervention was to reduce variation in lipid and amino acid metabolites, tricarboxylic acid (TCA) cycle intermediates, and acylcarnitines between the 2 PAPOLG genotypes. Conclusions: The metabolic changes observed with the HG broccoli diet are consistent with a rebalancing of anaplerotic and cataplerotic reactions and enhanced integration of fatty acid β-oxidation with TCA cycle activity. These modifications may contribute to the reduction in cancer risk associated with diets that are rich in cruciferous vegetables. This trial was registered at clinicaltrials.gov as NCT01114399. PMID:23964055

[Determination of lidocaine and its metabolites in human plasma by liquid chromatography in combination with tandem mass spectrometry].

Science.gov (United States)

Xiang, Jin; Zhang, Cheng; Yu, Qin; Liang, Mao-Zhi; Qin, Yong-Ping; Nan, Feng

2010-07-01

To establish a liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method for the determination of lidocaine (LDC) and its metabolites, monoethylglycinexylidide (MEGX) and glycinexylidide (GX), in human plasma. METHODS; The assay was conducted with an API 3000 HPLC-MS/MS system consisted of a Ultimate C18 column (50 x 4.6 mm, 5 microm). The mobile phase consisted of methanol: 5 mmol/ L ammonium acetate (50:50, pH was adjusted to 5.0 by formic acid) and the flow rate was set at 0.2 mL/min. The alkalinized sample was extracted with ethyl acetate. After evaporation of the organic layer, the residue was dissolved in mobile phase and the drug was determined by HPLC-MS/MS using electrospray ionization. The calibration curve was linear in a range from 15.625 to 2000 ng/mL for LDC. Linear calibration curves were obtained in the range of 1.5625 to 200 ng/mL for both for MEGX and GX. The limit of quantification for LDC, MEGX and GX was set at 15.625, 1.5625 and 1.5625 ng/mL. This method for the quantitative determination of lidocaine and its metabolites in human plasma is simple, rapid, sensitive and accurate. Therefore it can be used for the determination of lidocaine and its metabolites in clinical practice.

Effects of vitamin D3 supplementation and UVb exposure on the growth and plasma concentration of vitamin D3 metabolites in juvenile bearded dragons (Pogona vitticeps).

Science.gov (United States)

Oonincx, D G A B; Stevens, Y; van den Borne, J J G C; van Leeuwen, J P T M; Hendriks, W H

2010-06-01

The effectiveness of dietary vitamin D3 and UVb exposure on plasma vitamin D metabolites in growing bearded dragons (Pogona vitticeps) was studied. A total of 84 (40 males and 44 females) newly hatched bearded dragons were allocated to six levels of oral vitamin D3 supplementation (0 to 400%) or six UVb exposure times (2 to 12 h). At 3 and 6 months of age, blood samples were obtained from each animal and analysed for 25(OH)D3 and 1,25(OH)2D3. At 3 months of age, plasma concentrations of 25(OH)D3 did not increase with increasing vitamin D3 supplementation unlike the 1,25(OH)2D3. At 6 months of age, plasma concentrations of both 25(OH)D(3) and 1,25(OH)2D3 increased with increasing vitamin D(3) supplementation. Plasma concentrations in UVb-exposed animals were 18 times higher for 25(OH)D3 (178.4+/-9.0 vs. 9.9+/-1.3 nmol/L) and 5.3 times higher for 1,25(OH)2D3 (1.205+/-0.100 vs. 0.229+/-0.025 nmol/L) than in vitamin D(3) supplemented animals at 6 months of age. This study shows that 2h of UVb exposure enables adequate physiological concentrations of plasma vitamin D metabolites to be maintained in growing bearded dragons. Oral supplementation of vitamin D(3) is ineffective in raising plasma concentrations of 25(OH)D3 and 1,25(OH)2D3 to concentrations observed in UVb-exposed animals. 2010 Elsevier Inc. All rights reserved.

Gestational or acute restraint in adulthood reduces levels of 5α-reduced testosterone metabolites in the hippocampus and produces behavioral inhibition of adult male rats

Directory of Open Access Journals (Sweden)

Alicia A Walf

2012-12-01

Full Text Available Stressors, during early life or adulthood, can alter steroid-sensitive behaviors, such as exploration, anxiety, and/or cognitive processes. We investigated if exposure to acute stressors in adulthood may alter behavioral and neuroendocrine responses of male rats that were exposed to gestational stress or not. We hypothesized that rats exposed to gestational and acute stress may show behavioral inhibition, increased corticosterone, and altered androgen levels in the hippocampus. Subjects were adult, male offspring of rat dams that were restrained daily on gestational days 14-20, or did not experience this manipulation. Immediately before testing, rats were restraint-stressed for 20 minutes or not. During week 1, rats were tested in a battery of tasks, including the open field, elevated plus maze, social interaction, tailflick, pawlick, and defensive burying tasks. During week 2, rats were trained and tested 24 hours later in the inhibitory avoidance task. Plasma corticosterone and androgen levels, and hippocampal androgen levels, were measured in all subjects. Gestational and acute restraint stress increased plasma levels of corticosterone, and reduced levels of testosterone’s 5α-reduced metabolites, dihydrotestosterone and 3α-androstanediol, but not the aromatized metabolite, estradiol, in plasma or the hippocampus. Gestational and acute restraint stress reduced central entries made in the open field, and latencies to enter the shock-associated side of the inhibitory avoidance chamber during testing. Gestational stress reduced time spent interacting with a conspecific. These data suggest that gestational and acute restraint stress can have actions to produce behavioral inhibition coincident with increased corticosterone and decreased 5α-reduced androgens of adult male rats. Thus, gestational stress altered neural circuits involved in the neuroendocrine response to acute stress in early adulthood.

A unique automation platform for measuring low level radioactivity in metabolite identification studies.

Directory of Open Access Journals (Sweden)

Joel Krauser

Full Text Available Generation and interpretation of biotransformation data on drugs, i.e. identification of physiologically relevant metabolites, defining metabolic pathways and elucidation of metabolite structures, have become increasingly important to the drug development process. Profiling using (14C or (3H radiolabel is defined as the chromatographic separation and quantification of drug-related material in a given biological sample derived from an in vitro, preclinical in vivo or clinical study. Metabolite profiling is a very time intensive activity, particularly for preclinical in vivo or clinical studies which have defined limitations on radiation burden and exposure levels. A clear gap exists for certain studies which do not require specialized high volume automation technologies, yet these studies would still clearly benefit from automation. Use of radiolabeled compounds in preclinical and clinical ADME studies, specifically for metabolite profiling and identification are a very good example. The current lack of automation for measuring low level radioactivity in metabolite profiling requires substantial capacity, personal attention and resources from laboratory scientists. To help address these challenges and improve efficiency, we have innovated, developed and implemented a novel and flexible automation platform that integrates a robotic plate handling platform, HPLC or UPLC system, mass spectrometer and an automated fraction collector.

A Unique Automation Platform for Measuring Low Level Radioactivity in Metabolite Identification Studies

Science.gov (United States)

Krauser, Joel; Walles, Markus; Wolf, Thierry; Graf, Daniel; Swart, Piet

2012-01-01

Generation and interpretation of biotransformation data on drugs, i.e. identification of physiologically relevant metabolites, defining metabolic pathways and elucidation of metabolite structures, have become increasingly important to the drug development process. Profiling using 14C or 3H radiolabel is defined as the chromatographic separation and quantification of drug-related material in a given biological sample derived from an in vitro, preclinical in vivo or clinical study. Metabolite profiling is a very time intensive activity, particularly for preclinical in vivo or clinical studies which have defined limitations on radiation burden and exposure levels. A clear gap exists for certain studies which do not require specialized high volume automation technologies, yet these studies would still clearly benefit from automation. Use of radiolabeled compounds in preclinical and clinical ADME studies, specifically for metabolite profiling and identification are a very good example. The current lack of automation for measuring low level radioactivity in metabolite profiling requires substantial capacity, personal attention and resources from laboratory scientists. To help address these challenges and improve efficiency, we have innovated, developed and implemented a novel and flexible automation platform that integrates a robotic plate handling platform, HPLC or UPLC system, mass spectrometer and an automated fraction collector. PMID:22723932

Detecting beer intake by unique metabolite patterns

DEFF Research Database (Denmark)

Gürdeniz, Gözde; Jensen, Morten Georg; Meier, Sebastian

2016-01-01

Evaluation of health related effects of beer intake is hampered by the lack of accurate tools for assessing intakes (biomarkers). Therefore, we identified plasma and urine metabolites associated with recent beer intake by untargeted metabolomics and established a characteristic metabolite pattern...... representing raw materials and beer production as a qualitative biomarker of beer intake. In a randomized, crossover, single-blinded meal study (MSt1) 18 participants were given one at a time four different test beverages: strong, regular and non-alcoholic beers and a soft drink. Four participants were...... assigned to have two additional beers (MSt2). In addition to plasma and urine samples, test beverages, wort and hops extract were analyzed by UPLC-QTOF. A unique metabolite pattern reflecting beer metabolome, including metabolites derived from beer raw material (i.e. N-methyl tyramine sulfate and the sum...

Simultaneous quantification of lenalidomide, ibrutinib and its active metabolite PCI-45227 in rat plasma by LC-MS/MS: application to a pharmacokinetic study.

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Veeraraghavan, Sridhar; Viswanadha, Srikant; Thappali, Satheeshmanikandan; Govindarajulu, Babu; Vakkalanka, Swaroopkumar; Rangasamy, Manivannan

2015-03-25

Efficacy assessments using a combination of ibrutinib and lenalidomide necessitate the development of an analytical method for determination of both drugs in plasma with precision. A high performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed for the simultaneous determination of lenalidomide, ibrutinib, and its active metabolite PCI45227 in rat plasma. Extraction of lenalidomide, ibrutinib, PCI45227 and tolbutamide (internal standard; IS) from 50 μl rat plasma was carried out by liquid-liquid extraction with ethyl acetate:dichloromethane (90:10) ratio. Chromatographic separation of analytes was performed on YMC pack ODS AM (150 mm × 4.6 mm, 5 μm) column under gradient conditions with acetonitrile:0.1% formic acid buffer as the mobile phases at a flow rate of 1 ml/min. Precursor ion and product ion transition for analytes and IS were monitored on a triple quadrupole mass spectrometer, operated in the selective reaction monitoring with positive ionization mode. Method was validated over a concentration range of 0.72-183.20 ng/ml for ibrutinib, 0.76-194.33 ng/ml for PCI-45227 and 1.87-479.16 ng/ml for lenalidomide. Mean extraction recovery for ibrutinib, PCI-45227, lenalidomide and IS of 75.2%, 84.5%, 97.3% and 92.3% were consistent across low, medium, and high QC levels. Precision and accuracy at low, medium and high quality control levels were less than 15% across analytes. Bench top, wet, freeze-thaw and long term stability was evaluated for all the analytes. The analytical method was applied to support a pharmacokinetic study of simultaneous estimation of lenalidomide, ibrutinib, and its active metabolite PCI-45227 in Wistar rat. Assay reproducibility was demonstrated by re-analysis of 18 incurred samples. Copyright © 2014 Elsevier B.V. All rights reserved.

Haloperidol response and plasma catecholamines and their metabolites.

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Green, A I; Alam, M Y; Boshes, R A; Waternaux, C; Pappalardo, K M; Fitzgibbon, M E; Tsuang, M T; Schildkraut, J J

1993-06-01

Eleven acutely psychotic patients with schizophrenia or schizoaffective disorder underwent a 5-7 day drug-washout period (with lorazepam allowed) prior to participating in a 6-week controlled dose haloperidol trial. Patients were evaluated longitudinally with clinical ratings and with plasma measures of the catecholamines dopamine (pDA) and norepinephrine (pNE) and their metabolites, homovanillic acid (pHVA) and 3-methoxy-4-hydroxyphenylglycol (pMHPG). All patients exhibited clinical improvement with haloperidol; the decrease in their Brief Psychiatric Rating Scale (BPRS) scores ranged from 32 to 89%. Measures of pHVA increased within the first week of treatment and returned to baseline by week 5. The pattern of change of pDA resembled that of pHVA. The pattern of change of pNE and pMHPG revealed a decrease over the course of treatment. The early increase and the subsequent decrease in pHVA were strongly correlated with improvement in positive symptoms on the BPRS. These data are consistent with previous reports on the change in pHVA and pMHPG during clinical response to haloperidol. The data on change of pDA and pNE further describe the nature of the biochemical response to this drug.

Methionine Metabolites in Patients With Sepsis.

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Wexler, Orren; Gough, Michael S; Morgan, Mary Anne M; Mack, Cynthia M; Apostolakos, Michael J; Doolin, Kathleen P; Mooney, Robert A; Arning, Erland; Bottiglieri, Teodoro; Pietropaoli, Anthony P

2018-01-01

Sepsis is characterized by microvascular dysfunction and thrombophilia. Several methionine metabolites may be relevant to this sepsis pathophysiology. S-adenosylmethionine (SAM) serves as the methyl donor for trans-methylation reactions. S-adenosylhomocysteine (SAH) is the by-product of these reactions and serves as the precursor to homocysteine. Relationships between plasma total homocysteine concentrations (tHcy) and vascular disease and thrombosis are firmly established. We hypothesized that SAM, SAH, and tHcy levels are elevated in patients with sepsis and associated with mortality. This was a combined case-control and prospective cohort study consisting of 109 patients with sepsis and 50 control participants without acute illness. The study was conducted in the medical and surgical intensive care units of the University of Rochester Medical Center. Methionine, SAM, SAH, and tHcy concentrations were compared in patients with sepsis versus control participants and in sepsis survivors versus nonsurvivors. Patients with sepsis had significantly higher plasma SAM and SAH concentrations than control participants (SAM: 164 [107-227] vs73 [59-87 nM], P sepsis patients compared to healthy control participants (4 [2-6]) vs 7 [5-9] μM; P = .04). In multivariable analysis, quartiles of SAM, SAH, and tHcy were independently associated with sepsis ( P = .006, P = .05, and P Sepsis nonsurvivors had significantly higher plasma SAM and SAH concentrations than survivors (SAM: 223 [125-260] vs 136 [96-187] nM; P = .01; SAH: 139 [81-197] vs 86 [55-130] nM, P = .006). Plasma tHcy levels were similar in survivors vs nonsurvivors. The associations between SAM or SAH and hospital mortality were no longer significant after adjusting for renal dysfunction. Methionine metabolite concentrations are abnormal in sepsis and linked with clinical outcomes. Further study is required to determine whether these abnormalities have pathophysiologic significance.

Plasma thromboxane B2 levels in horses experimentally infected with Strongylus vulgaris.

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Cambridge, H; Reynoldson, J A; Dunsmore, J D

1989-06-01

Plasma thromboxane B2 (TXB2) the stable inactive metabolite of thromboxane A2 (TXA2), was measured daily by specific radioimmunoassay in three groups of animals before and after experimental infection with Strongylus vulgaris. Infection of four 'parasite naive' foals produced a typical acute syndrome with intermittent but statistically insignificant rises in TXB2 levels. Interpretation of results was complicated by the presence of a non-septic peritonitis associated with implantation of the foals with electrodes for recording myoelectrical activity. In two foals of similar age, with some natural exposure to S. vulgaris, there was little or no clinical response to infection and increases in TXB2 were absent. Baseline levels were also much lower, indicating that the peritonitis may have affected the results obtained in the first group of foals. Severe mesenteric arteritis was confirmed at necropsy in all six foals. A third group of yearling horses, all with natural exposure to the parasite, were generally resistant to infection. One animal developed arteritis with clinical signs of diarrhoea and mild colic, and also showed intermittent increases in TXB2. The mean plasma TXB2 level after infection was significantly higher than in the control period, although absolute levels were lower than those recorded in the 'parasite naive' foals. Other animals in this group had low TXB2 levels and minimal arteritis was found at necropsy. These results indicate that although infection appears to have an effect on plasma TXB2, the changes are inconsistent and not reliable indicators of the presence of verminous arteritis. The results also confirm the difficulty in establishing infection and the variability of the response in animals with previous exposure.

Evaluation of chlorpyrifos toxicity through a 28-day study: Cholinesterase activity, oxidative stress responses, parent compound/metabolite levels, and primary DNA damage in blood and brain tissue of adult male Wistar rats.

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Kopjar, Nevenka; Žunec, Suzana; Mendaš, Gordana; Micek, Vedran; Kašuba, Vilena; Mikolić, Anja; Lovaković, Blanka Tariba; Milić, Mirta; Pavičić, Ivan; Čermak, Ana Marija Marjanović; Pizent, Alica; Lucić Vrdoljak, Ana; Želježić, Davor

2018-01-05

In this 28 day-study, we evaluated the effects of the insecticide chlorpyrifos orally administered to Wistar rats at doses 0.160, 0.015, and 0.010 mg/kg b. w./day. Following treatment, total cholinesterase activity and activities of acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) were measured. Oxidative stress responses were evaluated using a battery of endpoints to establish lipid peroxidation, changes in total antioxidant capacity, level of reactive oxygen species (ROS), glutathione (GSH) level and activities of glutathione peroxidase (GSH-Px), superoxide dismutase (SOD) and catalase. Using HPLC-UV DAD analysis, levels of the parent compound and its main metabolite 3,5,6-trichloro-2-pyridinol in plasma and brain tissue were measured. The genotoxic effect was estimated using alkaline comet assay in leukocytes and brain tissue. The exposure did not result in significant effects on total cholinesterase, AChE and BChE activity in plasma and brain tissue. Lipid peroxidation slightly increased both in plasma and brain tissue. Total antioxidant capacity, ROS and GSH levels were marginally influenced by the exposure. Treatment led to significant increases of GSH-Px activity in blood, SOD activity in erythrocytes and a slight increase of catalase activity in plasma. HPLC-UV DAD analysis revealed the presence of both the parent compound and its main metabolite in the plasma of all of the experimental animals and brain tissue of the animals treated at the two higher doses. All of the tested doses of chlorpyrifos were slightly genotoxic, both to leukocytes and brain tissue. Our results call for further research using other sensitive biomarkers of effect, along with different exposure scenarios. Copyright © 2017 Elsevier B.V. All rights reserved.

Serum and Plasma Metabolomic Biomarkers for Lung Cancer.

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Kumar, Nishith; Shahjaman, Md; Mollah, Md Nurul Haque; Islam, S M Shahinul; Hoque, Md Aminul

2017-01-01

In drug invention and early disease prediction of lung cancer, metabolomic biomarker detection is very important. Mortality rate can be decreased, if cancer is predicted at the earlier stage. Recent diagnostic techniques for lung cancer are not prognosis diagnostic techniques. However, if we know the name of the metabolites, whose intensity levels are considerably changing between cancer subject and control subject, then it will be easy to early diagnosis the disease as well as to discover the drug. Therefore, in this paper we have identified the influential plasma and serum blood sample metabolites for lung cancer and also identified the biomarkers that will be helpful for early disease prediction as well as for drug invention. To identify the influential metabolites, we considered a parametric and a nonparametric test namely student׳s t-test as parametric and Kruskal-Wallis test as non-parametric test. We also categorized the up-regulated and down-regulated metabolites by the heatmap plot and identified the biomarkers by support vector machine (SVM) classifier and pathway analysis. From our analysis, we got 27 influential (p-value<0.05) metabolites from plasma sample and 13 influential (p-value<0.05) metabolites from serum sample. According to the importance plot through SVM classifier, pathway analysis and correlation network analysis, we declared 4 metabolites (taurine, aspertic acid, glutamine and pyruvic acid) as plasma biomarker and 3 metabolites (aspartic acid, taurine and inosine) as serum biomarker.

Effects of feeding metabolite combinations from lactobacillus plantarum on plasma and breast meat lipids in Broiler Chickens

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TC Loh

2013-12-01

Full Text Available The effects of feeding different doses of metabolite combination of L. plantarum RS5, RI11, RG14 and RG11 strains (Com3456 on cholesterol reduction in plasma and breast meat in broiler chickens and the possible mechanism was studied. A total of 504 male Ross broilers were grouped into 7 treatments and offered with different diets: (i standard corn-soybean based diet (-ve control; (ii standard cornsoybean based diet + neomycin and oxytetracycline (+ve control; (iii standard corn-soybean based diet + 0.1% metabolite combination of L. plantarum RS5, RI11, RG14 and RG11 strains (Com3456; (iv standard corn-soybean based diet + 0.2% of Com3456; (v standard cornsoybean based diet + 0.3% of Com3456 (vi standard corn-soybean based diet + 0.4% of Com3456 and (vii standard corn-soybean based diet + 0.5% of Com3456. The metabolite combinations supplemented in the diet of broilers reduced protein, cholesterol esters concentration in very low-density lipoprotein particles. The present of organic acids and proteinaceous compound in the metabolite combinations as found in previous study also increased lactic acid bacteria count in small intestine digesta and improved bile salts deconjugation ability of lactic acid bacteria.

Simultaneous determination of imperatorin and its 2 metabolites in dog plasma by using liquid chromatography-tandem mass spectrometry.

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Wang, Lu; Lu, Wen; Shen, Qi; Wang, Shengjia; Zhou, Hui; Yu, Lushan; Wang, Sicen; Jiang, Huidi; He, Langchong; Zeng, Su

2012-11-01

In this study, 2 metabolites of imperatorin, imperatorin hydroxylate (IMH) and imperatorin epoxide (IME), were identified for the first time in dog plasma. A sensitive, specific, and accurate high-performance liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was then developed for the simultaneous quantification of imperatorin and its 2 metabolites in dog plasma. Separation was achieved on an Agilent ZORBAX Extend-C(18) column (2.1 mm × 50 mm, 3.5 μm) at 30 °C. The mobile phase consisted of 0.02% ammonium acetate solution-methanol with a gradient program at a flow rate of 0.3 mL/min. Detection was performed using an electrospray ionization source operating in positive ion multiple reaction monitoring mode and by monitoring the ion transitions from 271 to 203 m/z for imperatorin, 309.4-224.1 m/z for IMH, 287-203 m/z for IME, and 441.3-325.2 m/z for simvastatin (the internal standard). Good linearity was shown over the concentration range of 1-500 ng/mL for imperatorin, and 0.2-500 ng/mL for IMH and IME. The validated method was successfully applied to a pharmacokinetic study of imperatorin in beagle dogs. The pharmacokinetic profiles of imperatorin and its 2 metabolites showed sex differences after the i.v. administration of imperatorin at a dose of 5 mg/kg. Copyright © 2012 Elsevier B.V. All rights reserved.

Clinical significance of determination of plasma CF6, 6-Keto-PGF1α and RLX levels in patients with preeclampsia

International Nuclear Information System (INIS)

Xu Fei; Chen Daozhen; Wang Junfeng; Yang Min; Pan Donghui

2010-01-01

Objective: To study the relationship between development of the disease and changes of plasma mitochondrial coupling factor 6 (CF6), prostacyclin (6-Keto-PGF 1α ) and relaxin (RLX) levels in patients with preeclampsia. Methods: Serum CF6, 6-Keto-PGF 1α (as the stable metabolite of 6-Keto-PGF 1α ) and relaxin levels were determined with RIA in (1) 22 pregnant women with mild pre-eclampsia (2) 20 pregnant women with severe pre-eclampsia and (3) 40 normal pregnant women (as controls). Results: The plasma levels of CF6 were significantly higher in patients with mild as well as severe preeclampsia than those in the controls (P 1α were only insignificantly decreased in patients with mild preeclampsia than those in the controls (P > 0.05). In severe preeclampsia group, plasma levels of 6-Keto-PGF 1α were significantly decreased than those in the controls (P 1α and RLX (r =-0.058, r =-0.601, all P 1α and RLX levels in patients with preeclampsia were helpful for assessment of progress of disease and outcome prediction. (authors)

Neurochemical metabolites in prefrontal cortex in patients with mild/moderate levels in first-episode depression

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Sozeri-Varma G

2013-08-01

Full Text Available Gülfizar Sözeri-Varma,1 Nalan Kalkan-Oğuzhanoglu,1 Muharrem Efe,1 Yilmaz Kiroglu,2 Taçlan Duman11Department of Psychiatry, 2Department of Radiology, Faculty of Medicine, Pamukkale University, Denizli, TurkeyBackground: Previous studies have determined the neurochemical metabolite abnormalities in major depressive disorder (MDD. The results of studies are inconsistent. Severity of depression may relate to neurochemical metabolic changes. The aim of this study is to investigate neurochemical metabolite levels in the prefrontal cortex (PFC of patients with mild/moderate MDD.Methods: Twenty-one patients with mild MDD, 18 patients with moderate MDD, and 16 matched control subjects participated in the study. Patients had had their first episode. They had not taken treatment. The severity of depression was assessed by the Hamilton Rating Scale for Depression (HAM-D. Levels of N-acetyl aspartate (NAA, choline-containing compounds (Cho, and creatine-containing compounds (Cr were measured using proton magnetic resonance spectroscopy (1H-MRS at 1.5 T, with an 8-cm3 single voxel placed in the right PFC.Results: The moderate MDD patients had lower NAA/Cr levels than the control group. No differences were found in neurochemical metabolite levels between the mild MDD and control groups. No correlation was found between the patients’ neurochemical metabolite levels and HAM-D scores.Conclusion: Our findings suggest that NAA/Cr levels are low in moderate-level MDD in the PFC. Neurochemical metabolite levels did not change in mild depressive disorder. Our results suggest that the severity of depression may affect neuronal function and viability. Studies are needed to confirm this finding, including studies on severely depressive patients.Keywords: major depressive disorder, magnetic resonance spectroscopy, N-acetyl aspartate, creatine, choline

New Modified UPLC/Tandem Mass Spectrometry Method for Determination of Risperidone and Its Active Metabolite 9-Hydroxyrisperidone in Plasma: Application to Dose-Dependent Pharmacokinetic Study in Sprague-Dawley Rats

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Essam Ezzeldin

2017-01-01

Full Text Available Sensitive and specific liquid-chromatography tandem mass spectrometry (UPLC-MS/MS assay has been developed and validated for simultaneous quantification of risperidone (RIS and its active metabolite 9-hydroxyrisperidone (9-OH-RIS in rat plasma using olanzapine (OLA as internal standard (IS. Pharmacokinetics of risperidone and its active metabolite 9-hydroxyrisperidone was compared across different doses (0.3, 1.0, and 6.0 mg/kg. Serial blood sample was collected over a time of 48 hours and analyzed for risperidone and its active metabolite 9-hydroxyrisperidone. The pharmacokinetics parameters including Cmax, tmax, and AUC were determined for risperidone and its active ingredient. The method was linear in the concentration range of 0.2–500 ng/mL for risperidone and 9-OH-risperidone, with coefficients of determination greater than 0.998 and lower limit of quantitation of 0.2 ng/mL. Blood levels of risperidone and its active metabolite were roughly dose-proportional. The method developed herein is simple and rapid and was successfully applied for dose-dependent pharmacokinetic study.

Metabolites Identified during Varied Doses of Aspergillus Species in Zea mays Grains, and Their Correlation with Aflatoxin Levels

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Titilayo D. O. Falade

2018-05-01

Full Text Available Aflatoxin contamination is associated with the development of aflatoxigenic fungi such as Aspergillus flavus and A. parasiticus on food grains. This study was aimed at investigating metabolites produced during fungal development on maize and their correlation with aflatoxin levels. Maize cobs were harvested at R3 (milk, R4 (dough, and R5 (dent stages of maturity. Individual kernels were inoculated in petri dishes with four doses of fungal spores. Fungal colonisation, metabolite profile, and aflatoxin levels were examined. Grain colonisation decreased with kernel maturity: milk-, dough-, and dent-stage kernels by approximately 100%, 60%, and 30% respectively. Aflatoxin levels increased with dose at dough and dent stages. Polar metabolites including alanine, proline, serine, valine, inositol, iso-leucine, sucrose, fructose, trehalose, turanose, mannitol, glycerol, arabitol, inositol, myo-inositol, and some intermediates of the tricarboxylic acid cycle (TCA—also known as citric acid or Krebs cycle were important for dose classification. Important non-polar metabolites included arachidic, palmitic, stearic, 3,4-xylylic, and margaric acids. Aflatoxin levels correlated with levels of several polar metabolites. The strongest positive and negative correlations were with arabitol (R = 0.48 and turanose and (R = −0.53, respectively. Several metabolites were interconnected with the TCA; interconnections of the metabolites with the TCA cycle varied depending upon the grain maturity.

High-performance liquid chromatographic determination of certain salicylates and their major metabolites in plasma following topical administration of a liniment to healthy subjects.

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Dadgar, D; Climax, J; Lambe, R; Darragh, A

1985-08-09

The liniment used is a topical analgesic and anti-inflammatory preparation containing two active constituents, 3-phenylpropylsalicylate and ethyl-5-methoxysalicylate, in solution in isobutyl decanoate. It is known that 3-phenylpropylsalicylate is metabolised to salicylic acid and salicyluric acid and ethyl-5-methoxysalicylate is metabolised to 5-methoxysalicylic acid and gentisic acid. In the present study the separation of the salicylates and their metabolites was carried out on a Waters mu Bondapak C18 column using two different mobile phases, methanol-water (80:20) for the parent drugs and methanol-5% aqueous acetic acid (27:73) for their metabolites. The salicylates and their metabolites were detected by absorption at 310 nm. The limits of detection for parent drugs and metabolites were respectively 0.2 and 0.1 microgram/ml in plasma, using a 1-ml plasma sample and a 20-microliter injection from a reconstituted volume of 250 microliter. Mean percentage coefficients of variation for intra-assay and inter-assay precision were between 3.3 +/- 1.9% to 9.1 +/- 3.7% and 6.8 +/- 2.2% to 15.7 +/- 10.1%, respectively. Linearity, as measured by the correlation coefficient of intra-assay linear regression curves, was better than 0.998 in all cases.

In matrix derivatization of trichloroethylene metabolites in human plasma with methyl chloroformate and their determination by solid-phase microextraction-gas chromatography-electron capture detector.

Science.gov (United States)

Mudiam, Mohana Krishna Reddy; Jain, Rajeev; Varshney, Meenu; Ch, Ratnasekhar; Chauhan, Abhishek; Goyal, Sudhir Kumar; Khan, Haider A; Murthy, R C

2013-04-15

Trichloroethylene (TCE) is a common industrial chemical that has been widely used as metal degreaser and for many industrial purposes. In humans, TCE is metabolized into dichloroacetic acid (DCA), trichloroacetic acid (TCA) and trichloroethanol (TCOH). A simple and rapid method has been developed for the quantitative determination of TCE metabolites. The procedure involves the in situ derivatization of TCE metabolites with methyl chloroformate (MCF) directly in diluted plasma samples followed by extraction and analysis with solid-phase microextraction (SPME) coupled to gas chromatography-electron capture detector (GC-ECD). Factors which can influence the efficiency of derivatization such as amount of MCF and pyridine (PYR), ratio of water/methanol were optimized. The factors which can affect the extraction efficiencies of SPME were screened using 2(7-4) Placket-Burman Design (PBD). A central composite design (CCD) was then applied to further optimize the most significant factors for optimum SPME extraction. The optimum factors for the SPME extraction were found to be 562.5mg of NaCl, pH at 1 and an extraction time of 22 min. Recoveries and detection limits of all three analytes in plasma were found to be in the range of 92.69-97.55% and 0.036-0.068 μg mL(-1) of plasma, respectively. The correlation coefficients were found to be in the range of 0.990-0.995. The intra- and inter-day precisions for TCE metabolites were found to be in the range of 2.37-4.81% and 5.13-7.61%, respectively. The major advantage of this method is that MCF derivatization allows conversion of TCE metabolites into their methyl esters in very short time (≤30 s) at room temperature directly in the plasma samples, thus makes it a solventless analysis. The method developed was successfully applied to the plasma samples of humans exposed to TCE. Copyright © 2013 Elsevier B.V. All rights reserved.

Effects of profession on urinary PAH metabolite levels in the US population.

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Liu, Bian; Jia, Chunrong

2016-01-01

Although exposure to polycyclic aromatic hydrocarbons (PAHs) is common in both environmental and occupational settings, few studies have compared PAH exposure among people with different professions. The purpose of this study was to investigate the variations in recent PAH exposure among different occupational groups over time using national representative samples. The study population consisted of 4162 participants from the 2001 to 2008 National Health and Nutrition Examination Survey, who had both urinary PAH metabolites and occupational information. Four corresponding monohydroxy-PAH urine metabolites: naphthalene (NAP), fluorene (FLUO), phenanthrene (PHEN), and pyrene (PYR) among seven broad occupational groups were analyzed using weighted linear regression models, adjusting for creatinine levels, sociodemographic factors, smoking status, and sampling season. The overall geometric mean concentrations of NAP, FLUO, PHEN, and PYR were 6927, 477, 335, and 87 ng/L, respectively. All four PAH metabolites were elevated in the "extractive, construction, and repair (ECR)" group, with 21-42 % higher concentrations than those in the reference group of "management." Similar trends were seen in the "operators, fabricators, and laborers (OFL)" group for FLUO, PHEN, and PYR. In addition, both "service" and "support" groups had elevated FLUO. Significant (p PAH exposure. Heterogeneous distributions of urinary PAH metabolites among people with different job categories exist at the population level. The upward temporal trends in NAP and PYR warrant reduction in PAH exposure, especially among those with OFL and ECR occupations.

Longitudinal plasma metabolic profiles, infant feeding, and islet autoimmunity in the MIDIA study.

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Jørgenrud, Benedicte; Stene, Lars C; Tapia, German; Bøås, Håkon; Pepaj, Milaim; Berg, Jens P; Thorsby, Per M; Orešič, Matej; Hyötyläinen, Tuulia; Rønningen, Kjersti S

2017-03-01

The aim of this study was to investigate the longitudinal plasma metabolic profiles in healthy infants and the potential association with breastfeeding duration and islet autoantibodies predictive of type 1 diabetes. Up to four longitudinal plasma samples from age 3 months from case children who developed islet autoimmunity (n = 29) and autoantibody-negative control children (n = 29) with the HLA DR4-DQ8/DR3-DQ2 genotype were analyzed using two-dimensional gas chromatography coupled to a time-of-flight mass spectrometer for detection of small polar metabolites. Plasma metabolite levels were found to depend strongly on age, with fold changes varying up to 50% from age 3 to 24 months (p polar metabolites changed with age during early childhood, independent of later islet autoimmunity status and sex. Breastfeeding was associated with higher levels of branched-chain amino acids, and lower levels of methionine and 3,4-dihydroxybutyric acid. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

Blood metabolites and some fertility parameters in dairy cows under intensive management system

International Nuclear Information System (INIS)

Osman, Awad Ali

1998-08-01

Dairy farms (1, 2, 3 and 4) of the intensive management system were selected. They are located 50 kilometers south of Khartoum state in a semi-arid zone. The effect of management on some fertility parameters, blood metabolites and minerals were investigated. Changes in blood metabolites with stage of lactation were also monitored. Other parameters studied were body weight, body condition score at calving. The results revealed that days to first P 4 rise after calving and number of services per conception (NSPC) were lower in the farm s contained the cross-bred (Fresian X Zebu) compared to the farm contained the pure Fresian breed. The pure Fresian cows showed heavier weights and less body score at calving compared to the cross breed. Blood metabolites reflected the nutritional status of the dairy cows under study, plasma total protein, albumin, globulin, urea and Glucose did not show significant changes either either either between farms or in response to lactation stages. However, high levels of Globulins might indicate inflammation due to some diseases such as mastitis, metritis and lameness. Plasma level of Calcium and Phosphorous did not change significantly either between farms or due to stages of lactation.(Author)

A parallel chiral-achiral liquid chromatographic method for the determination of the stereoisomers of ketamine and ketamine metabolites in the plasma and urine of patients with complex regional pain syndrome.

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Moaddel, Ruin; Venkata, Swarajya Lakshmi Vattem; Tanga, Mary J; Bupp, James E; Green, Carol E; Iyer, Lalitha; Furimsky, Anna; Goldberg, Michael E; Torjman, Marc C; Wainer, Irving W

2010-10-15

A parallel chiral/achiral LC-MS/MS assay has been developed and validated to measure the plasma and urine concentrations of the enantiomers of ketamine, (R)- and (S)-Ket, in complex regional pain syndrome (CRPS) patients receiving a 5-day continuous infusion of a sub-anesthetic dose of (R,S)-Ket. The method was also validated for the determination of the enantiomers of the Ket metabolites norketamine, (R)- and (S)-norKet and dehydronorketamine, (R)- and (S)-DHNK, as well as the diastereomeric metabolites hydroxynorketamine, (2S,6S)-/(2R,6R)-HNK and two hydroxyketamines, (2S,6S)-HKet and (2S,6R)-Hket. In this method, (R,S)-Ket, (R,S)-norKet and (R,S)-DHNK and the diastereomeric hydroxyl-metabolites were separated and quantified using a C(18) stationary phase and the relative enantiomeric concentrations of (R,S)-Ket, (R,S)-norKet and (R,S)-DHNK were determined using an AGP-CSP. The analysis of the results of microsomal incubations of (R)- and (S)-Ket and a plasma and urine sample from a CRPS patient indicated the presence of 10 additional compounds and glucuronides. The data from the analysis of the patient sample also demonstrated that a series of HNK metabolites were the primary metabolites in plasma and (R)- and (S)-DHNK were the major metabolites found in urine. The results suggest that norKet is the initial, but not the primary metabolite and that downstream norKet metabolites play a role in (R,S)-Ket-related pain relief in CRPS patients. Published by Elsevier B.V.

Serum level of hormone and metabolites in pregnant rabbit does

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Gabriele Brecchia

2010-01-01

Full Text Available The aims of this study were to compare the hormones and metabolites serum levels and the reproductive performances of nulliparous (n=100 and primiparous pregnant does submitted to artificial insemination (AI 11 days post-partum. On the day of AI, all the does were weighed and the sexual receptivity was evaluated. The kits were weaned at 26 day. Blood samples were collect by punc- ture of the marginal ear vein from one day before AI until few days before the kindling and assayed for hormones and metabolites. The higher sexual receptivity and the fertility in nulliparous than in primiparous does confirmed the negative effect of lactation. Nulliparous does showed higher blood con- centration of leptine than primiparous, and in both the groups such level lowered during pregnancy, probably reflecting the reduction of the fat reserve. The insuline level increased during pregnancy in either groups as a consequence of the growing of the foetuses. In nulliparous does the cortisol, NEFA and T3 concentrations were higher than primiparous does. The glucose levels were similar in both the groups probably due to the homeostatic mechanisms controlling the glycemia. Hormonal and metabo- lite analyses represent a good tool for understanding the physiological mechanisms required to meet higher reproductive performance.

Benzene metabolite levels in blood and bone marrow of B6C3F{sub 1} mice after low-level exposure

Energy Technology Data Exchange (ETDEWEB)

Bechtold, W.E.; Strunk, M.R.; Thornton-Manning, J.R. [and others

1995-12-01

Studies at the Inhalation Toxicology Research Institute (ITRI) have explored the species-specific uptake and metabolism of benzene. Results have shown that metabolism is dependent on both dose and route of administration. Of particular interest were shifts in the major metabolic pathways as a function of exposure concentration. In these studies, B6C3F{sub 1} mice were exposed to increasing levels of benzene by either gavage or inhalation. As benzene internal dose increased, the relative amounts of muconic acid and hydroquinone decreased. In contrast, the relative amount of catechol increased with increasing exposure. These results show that the relative levels of toxic metabolites are a function of exposure level. Based on these results and assuming a linear relationship between exposure concentration and levels of bone marrow metabolites, it would be difficult to detect an elevation of any phenolic metabolites above background after occupational exposures to the OSHA Permissible Exposure Limit of 1 ppm benzene.

Relationships of Cerebrospinal Fluid Monoamine Metabolite Levels With Clinical Variables in Major Depressive Disorder.

Science.gov (United States)

Yoon, Hyung Shin; Hattori, Kotaro; Ogawa, Shintaro; Sasayama, Daimei; Ota, Miho; Teraishi, Toshiya; Kunugi, Hiroshi

Many studies have investigated cerebrospinal fluid (CSF) monoamine metabolite levels in depressive disorders. However, their clinical significance is still unclear. We tried to determine whether CSF monoamine metabolite levels could be a state-dependent marker for major depressive disorder (MDD) based on analyses stratified by clinical variables in a relatively large sample. Subjects were 75 patients with MDD according to DSM-IV criteria and 87 healthy controls, matched for age, sex, and ethnicity (Japanese). They were recruited between May 2010 and November 2013. We measured homovanillic acid (HVA), 5-hydroxyindoleacetic acid (5-HIAA), and 3-methoxy-4-hydroxyphenylethyleneglycol (MHPG) in CSF samples by high-performance liquid chromatography. We analyzed the relationships of the metabolite levels with age, sex, diagnosis, psychotropic medication use, and depression severity. There was a weak positive correlation between age and 5-HIAA levels in controls (ρ = 0.26, P 12) were significantly lower than those in controls (P .1), were related to depression severity. CSF 5-HIAA and HVA levels could be state-dependent markers in MDD patients. Since 5-HIAA levels greatly decrease with the use of antidepressants, HVA levels might be more useful in the clinical setting. © Copyright 2017 Physicians Postgraduate Press, Inc.

Plasma orexin A levels in recently menopausal women during and 3 years following use of hormone therapy.

Science.gov (United States)

Cintron, Dahima; Beckman, John P; Bailey, Kent R; Lahr, Brian D; Jayachandran, Muthuvel; Miller, Virginia M

2017-05-01

Alterations in sleep quality and metabolism during menopause are improved by menopausal hormone therapy (MHT). The mechanisms mediating these effects remain unclear. Orexin A (OxA) is a neuro-peptide that regulates sleep/wakefulness, food intake and metabolism. This study examined changes in plasma OxA levels during and after treatment in women from the Kronos Early Estrogen Prevention Study (KEEPS). KEEPS randomized women within three years of menopause to: oral conjugated equine estrogen (o-CEE, 0.45mg/day), transdermal 17β estradiol (t-E2, 50μg/day), or placebo pills and patches for four years. Plasma OxA levels were measured by enzyme immunoassays in fasting blood samples collected annually from KEEPS participants at Mayo Clinic during and three years after MHT. Changes in menopausal symptoms and plasma OxA levels were assessed for treatment differences. During treatment, OxA levels increased more in women randomized to o-CEE compared with the other groups. Women randomized to either form of MHT demonstrated smaller increases in BMI than those on placebo. Insomnia severity decreased similarly among treatment groups. However, neither changes in sleep nor changes in BMI correlated with changes in plasma OxA levels. Changes in waist circumference correlated positively with changes in plasma OxA levels three years after discontinuation of study treatments. Although OxA levels increased only in women randomized to o-CEE, these changes did not correlate with changes in sleep quality or BMI. The modest correlation of OxA levels with waist circumference once study treatments were discontinued suggests that OxA may be modulated through multiple intermediary pathways affected by metabolites of 17β-estradiol. Clinical Trial Registration for KEEPS: NCT00154180. Copyright © 2017. Published by Elsevier B.V.

Limited predictive value of achieving beneficial plasma (Z)-endoxifen threshold level by CYP2D6 genotyping in tamoxifen-treated Polish women with breast cancer

International Nuclear Information System (INIS)

Hennig, Ewa E.; Piatkowska, Magdalena; Karczmarski, Jakub; Goryca, Krzysztof; Brewczynska, Elzbieta; Jazwiec, Radoslaw; Kluska, Anna; Omiotek, Robert; Paziewska, Agnieszka; Dadlez, Michal; Ostrowski, Jerzy

2015-01-01

Tamoxifen, the most frequently used drug for treating estrogen receptor-positive breast cancer, must be converted into active metabolites to exert its therapeutic efficacy, mainly through CYP2D6 enzymes. The objective of this study was to investigate the impact of CYP2D6 polymorphisms on (Z)-endoxifen-directed tamoxifen metabolism and to assess the usefulness of CYP2D6 genotyping for identifying patients who are likely to have insufficient (Z)-endoxifen concentrations to benefit from standard therapy. Blood samples from 279 Polish women with breast cancer receiving tamoxifen 20 mg daily were analyzed for CYP2D6 genotype and drug metabolite concentration. Steady-state plasma levels of tamoxifen and its 14 metabolites were measured by using the ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) method. In nearly 60 % of patients, including over 30 % of patients with fully functional CYP2D6, (Z)-endoxifen concentration was below the predefined threshold of therapeutic efficacy. The most frequently observed CYP2D6 genotype was EM/PM (34.8 %), among which 83.5 % of patients had a combination of wild-type and *4 alleles. Plasma concentration of five metabolites was significantly correlated with CYP2D6 genotype. For the first time, we identified an association between decreased (E/Z)-4-OH-N-desmethyl-tamoxifen-β-D-glucuronide levels (r 2 = 0.23; p < 10 −16 ) and increased CYP2D6 functional impairment. The strongest correlation was observed for (Z)-endoxifen, whose concentration was significantly lower in groups of patients carrying at least one CYP2D6 null allele, compared with EM/EM patients. The CYP2D6 genotype accounted for plasma level variability of (Z)-endoxifen by 27 % (p < 10 −16 ) and for the variability of metabolic ratio indicating (Z)-endoxifen-directed metabolism of tamoxifen by 51 % (p < 10 −43 ). The majority of breast cancer patients in Poland may not achieve a therapeutic level of (Z)-endoxifen upon receiving a standard

Peripheral metabolism of [18F]FDDNP and cerebral uptake of its labelled metabolites

International Nuclear Information System (INIS)

Luurtsema, Gert; Schuit, Robert C.; Takkenkamp, Kevin; Lubberink, Mark; Hendrikse, N. Harry; Windhorst, Albert D.; Molthoff, Carla F.M.; Tolboom, Nelleke; Berckel, Bart N.M. van; Lammertsma, Adriaan A.

2008-01-01

[ 18 F]FDDNP is a positron emission tomography (PET) tracer for determining amyloid plaques and neurofibrillary tangles in the brain in vivo. In order to quantify binding of this tracer properly, a metabolite-corrected plasma input function is required. The purpose of the present study was to develop a sensitive method for measuring [ 18 F]FDDNP and its radiolabelled metabolites in plasma. The second aim was to assess whether these radiolabelled metabolites enter the brain. In humans, there was extensive metabolism of [ 18 F]FDDNP. After 10 min, more than 80% of plasma radioactivity was identified as polar 18 F-labelled fragments, probably formed from N-dealkylation of [ 18 F]FDDNP. These labelled metabolites were reproduced in vitro using human hepatocytes. PET studies in rats showed that these polar metabolites can penetrate the blood-brain barrier and result in uniform brain uptake

Fluoride absorption: independence from plasma fluoride levels

International Nuclear Information System (INIS)

Whitford, G.M.; Williams, J.L.

1986-01-01

The concept that there are physiologic mechanisms to homeostatically regulate plasma fluoride concentrations has been supported by results in the literature suggesting an inverse relationship between plasma fluoride levels and the absorption of the ion from the gastrointestinal tract of the rat. The validity of the relationship was questioned because of possible problems in the experimental design. The present work used four different methods to evaluate the effect of plasma fluoride levels on the absorption of the ion in rats: (i) the percentage of the daily fluoride intake that was excreted in the urine; (ii) the concentration of fluoride in femur epiphyses; (iii) the net areas under the time-plasma fluoride concentration curves after intragastric fluoride doses; and (iv) the residual amounts or fluoride in the gastrointestinal tracts after the intragastric fluoride doses. None of these methods indicated that plasma fluoride levels influence the rate or the degree or fluoride absorption. It was concluded that, unless extremely high plasma fluoride levels are involved (pharmacologic or toxic doses), the absorption of the ion is independent of plasma levels. The results provide further evidence that plasma fluoride concentrations are not homeostatically regulated

Influence of heparin on the assay of amitriptyline, clomipramine, and their metabolites

NARCIS (Netherlands)

Levering, S.C.M.; Oostelbos, M.C.J.M.; Toll, P.J.M.M.; Loonen, A.J.M.

1996-01-01

In this study the effect of the use of lithium heparin containers on the plasma levels of amitriptyline, clomipramine, and their metabolites was investigated. Twenty-five patients (10 men and 15 women, mean age 51.8 ± 14.9 years) taking either amitriptyline or clomipramine in a daily dosage varying

Circulating prostacyclin metabolites in the dog

International Nuclear Information System (INIS)

Taylor, B.M.; Shebuski, R.J.; Sun, F.F.

1983-01-01

The present study was designed to determine the concentration of prostacyclin (PGI2) metabolites in the blood of the dog. After a bolus i.v. dose of [11 beta- 3 H]PGI2 (5 micrograms/kg) into each of five dogs, blood samples were withdrawn at 0.33, 0.67, 1, 3, 5, 20, 30, 60 and 120 min postdrug administration. Plasma samples were extracted and the radioactive components were analyzed by two-dimensional thin-layer chromatography with autoradiofluorography and radio-high-performance liquid chromatography. The compounds were identified by comparing their mobility with synthetic standards; only parallel responses observed in both tests constituted positive identification. Seven metabolites were identified by these two techniques: 6-keto-prostaglandin (PG)F1 alpha; 6-keto-PGE1; 2,3-dinor-6-keto-PGF 1 alpha; 2,3-dinor-13,14-dihydro-6,15-diketo-20-carboxyl PGF 1 alpha; and 2,3,18,19-tetranor-13,14-dihydro-6,15-diketo-20-carboxyl PGF 1 alpha. Several additional compounds, both polar and nonpolar in nature, which did not co-chromatograph with any of our standards were also detected. Early samples consisted predominantly of 6-keto-PGF 1 alpha and other 20-carbon metabolites. By 30 min, the predominant metabolites were the 16- and 18-carbon dicarboxylic acids. By 60 min, 85% of the radioactivity was associated with two unidentified polar compounds. The evidence suggests that 6-keto-PGF 1 alpha probably reflects only the transient levels of freshly entering PGI2 in the circulation, whereas levels of the most polar metabolites (e.g., dihydro-diketo-carboxyl tetranor-PGF 2 alpha) may be a better measure of the overall PGI2 presence due to its longer half-life in circulation

Plasma levels of antiprogestin RU 486 following oral administration to non-pregnant and early pregnant women

International Nuclear Information System (INIS)

Swahn, M.L.; Wang, G.; Aedo, A.R.; Cekan, S.Z.; Bygdeman, M.

1986-01-01

RU 486 is a synthetic steroid which acts as an antiprogestin at the receptor level. The clinical usefulness of the compound for menstrual regulation and termination of early pregnancy is currently being evaluated. The aim of the present study was to determine the plasma levels of RU 486 following the oral administration of the compound to 42 pregnant and 10 non-pregnant women. The levels of RU 486 were measured by a radioimmunoassay method which uses chromatography on Sephadex LH 20 columns. The identity of the compound assayed as RU 486 was confirmed, but the presence of small amounts of two highly cross-reacting metabolites (monodemethyl and didemethyl RU 486) in the analyzed fractions could not be excluded. Following the ingestion of a single tablet containing 25 and 50 mg of the compound, a peak plasma value of approximately 3.5 to 4.0 mumol/l in both the pregnant and non-pregnant subjects was reached one to two hours later. The half-lives of elimination were about 20 hours in both the pregnant and the non-pregnant women. Following the repeated oral administration of 50, 100 or 200 mg of RU 486 daily for four days, maximum plasma levels of 2.9, 4.5 and 5.4 mumol/l, respectively, were found. Thus, the increase in plasma levels was not directly proportional to the increase in the dose. No accumulation of RU 486 in the plasma was found, even when the duration of treatment was prolonged to six days. The data partly explain the reported lack of relation between ingested dose and frequency of induced abortion and they may be useful for designing future studies on the use of compound to prevent implantation, induce menstruation or terminate an early pregnancy

Plasma levels of antiprogestin RU 486 following oral administration to non-pregnant and early pregnant women

Energy Technology Data Exchange (ETDEWEB)

Swahn, M.L.; Wang, G.; Aedo, A.R.; Cekan, S.Z.; Bygdeman, M.

1986-11-01

RU 486 is a synthetic steroid which acts as an antiprogestin at the receptor level. The clinical usefulness of the compound for menstrual regulation and termination of early pregnancy is currently being evaluated. The aim of the present study was to determine the plasma levels of RU 486 following the oral administration of the compound to 42 pregnant and 10 non-pregnant women. The levels of RU 486 were measured by a radioimmunoassay method which uses chromatography on Sephadex LH 20 columns. The identity of the compound assayed as RU 486 was confirmed, but the presence of small amounts of two highly cross-reacting metabolites (monodemethyl and didemethyl RU 486) in the analyzed fractions could not be excluded. Following the ingestion of a single tablet containing 25 and 50 mg of the compound, a peak plasma value of approximately 3.5 to 4.0 mumol/l in both the pregnant and non-pregnant subjects was reached one to two hours later. The half-lives of elimination were about 20 hours in both the pregnant and the non-pregnant women. Following the repeated oral administration of 50, 100 or 200 mg of RU 486 daily for four days, maximum plasma levels of 2.9, 4.5 and 5.4 mumol/l, respectively, were found. Thus, the increase in plasma levels was not directly proportional to the increase in the dose. No accumulation of RU 486 in the plasma was found, even when the duration of treatment was prolonged to six days. The data partly explain the reported lack of relation between ingested dose and frequency of induced abortion and they may be useful for designing future studies on the use of compound to prevent implantation, induce menstruation or terminate an early pregnancy.

Plasma Metabolomics Biosignature According to HIV Stage of Infection, Pace of Disease Progression, Viremia Level and Immunological Response to Treatment.

Directory of Open Access Journals (Sweden)

Bruno Scarpellini

Full Text Available We evaluated plasma samples HIV-infected individuals with different phenotypic profile among five HIV-infected elite controllers and five rapid progressors after recent HIV infection and one year later and from 10 individuals subjected to antiretroviral therapy, five of whom were immunological non-responders (INR, before and after one year of antiretroviral treatment compared to 175 samples from HIV-negative patients. A targeted quantitative tandem mass spectrometry metabolomics approach was used in order to determine plasma metabolomics biosignature that may relate to HIV infection, pace of HIV disease progression, and immunological response to treatment.Twenty-five unique metabolites were identified, including five metabolites that could distinguish rapid progressors and INRs at baseline. Severe deregulation in acylcarnitine and sphingomyelin metabolism compatible with mitochondrial deficiencies was observed. β-oxidation and sphingosine-1-phosphate-phosphatase-1 activity were down-regulated, whereas acyl-alkyl-containing phosphatidylcholines and alkylglyceronephosphate synthase levels were elevated in INRs. Evidence that elite controllers harbor an inborn error of metabolism (late-onset multiple acyl-coenzyme A dehydrogenase deficiency [MADD] was detected.Blood-based markers from metabolomics show a very high accuracy of discriminating HIV infection between varieties of controls and have the ability to predict rapid disease progression or poor antiretroviral immunological response. These metabolites can be used as biomarkers of HIV natural evolution or treatment response and provide insight into the mechanisms of the disease.

Plasma Metabolomics Biosignature According to HIV Stage of Infection, Pace of Disease Progression, Viremia Level and Immunological Response to Treatment.

Science.gov (United States)

Scarpellini, Bruno; Zanoni, Michelle; Sucupira, Maria Cecilia Araripe; Truong, Hong-Ha M; Janini, Luiz Mario Ramos; Segurado, Ismael Dale Cotrin; Diaz, Ricardo Sobhie

2016-01-01

We evaluated plasma samples HIV-infected individuals with different phenotypic profile among five HIV-infected elite controllers and five rapid progressors after recent HIV infection and one year later and from 10 individuals subjected to antiretroviral therapy, five of whom were immunological non-responders (INR), before and after one year of antiretroviral treatment compared to 175 samples from HIV-negative patients. A targeted quantitative tandem mass spectrometry metabolomics approach was used in order to determine plasma metabolomics biosignature that may relate to HIV infection, pace of HIV disease progression, and immunological response to treatment. Twenty-five unique metabolites were identified, including five metabolites that could distinguish rapid progressors and INRs at baseline. Severe deregulation in acylcarnitine and sphingomyelin metabolism compatible with mitochondrial deficiencies was observed. β-oxidation and sphingosine-1-phosphate-phosphatase-1 activity were down-regulated, whereas acyl-alkyl-containing phosphatidylcholines and alkylglyceronephosphate synthase levels were elevated in INRs. Evidence that elite controllers harbor an inborn error of metabolism (late-onset multiple acyl-coenzyme A dehydrogenase deficiency [MADD]) was detected. Blood-based markers from metabolomics show a very high accuracy of discriminating HIV infection between varieties of controls and have the ability to predict rapid disease progression or poor antiretroviral immunological response. These metabolites can be used as biomarkers of HIV natural evolution or treatment response and provide insight into the mechanisms of the disease.

Plasma homocysteine levels in multiple sclerosis

NARCIS (Netherlands)

Ramsaransing, G S M; Fokkema, M R; Teelken, A; Arutjunyan, A V; Koch, M; De Keyser, J

Background: There is evidence that homocysteine contributes to various neurodegenerative disorders, and elevated plasma homocysteine levels have been observed in patients with multiple sclerosis (MS). Objective: To investigate if and why plasma homocysteine levels are increased in MS, and whether

Decrease in plasma high-density lipoprotein cholesterol levels at puberty in boys with delayed adolescence: correlation with plasma testosterone levels

International Nuclear Information System (INIS)

Kirkland, R.T.; Keenan, B.S.; Probstfield, J.L.; Patsch, W.; Lin, T.L.; Clayton, G.W.; Insull, W. Jr.

1987-01-01

A three-phase study tested the hypothesis that the decrease in the high-density lipoprotein cholesterol (HDL-C) level observed in boys at puberty is related to an increase in the plasma testosterone concentration. In phase I, 57 boys aged 10 to 17 years were categorized into four pubertal stages based on clinical parameters and plasma testosterone levels. These four groups showed increasing plasma testosterone values and decreasing HDL-C levels. In phase II, 14 boys with delayed adolescence were treated with testosterone enanthate. Plasma testosterone levels during therapy were in the adult male range. Levels of HDL-C decreased by a mean of 7.4 mg/dL (0.20 mmol/L) and 13.7 mg/dL (0.35 mmol/L), respectively, after the first two doses. In phase III, 13 boys with delayed adolescence demonstrated increasing plasma testosterone levels and decreasing HDL-C levels during spontaneous puberty. Levels of HDL-C and apolipoprotein A-1 were correlated during induced and spontaneous puberty. Testosterone should be considered a significant determinant of plasma HDL-C levels during pubertal development

Blood metabolites and some fertility parameters in dairy cows under intensive management system

Energy Technology Data Exchange (ETDEWEB)

Osman, Awad Ali [Faculty of Animal Production, University of Khartoum, Khartoum (Sudan)

1998-08-01

Dairy farms (1, 2, 3 and 4) of the intensive management system were selected. They are located 50 kilometers south of Khartoum state in a semi-arid zone. The effect of management on some fertility parameters, blood metabolites and minerals were investigated. Changes in blood metabolites with stage of lactation were also monitored. Other parameters studied were body weight, body condition score at calving. The results revealed that days to first P{sup 4} rise after calving and number of services per conception (NSPC) were lower in the farm s contained the cross-bred (Fresian X Zebu) compared to the farm contained the pure Fresian breed. The pure Fresian cows showed heavier weights and less body score at calving compared to the cross breed. Blood metabolites reflected the nutritional status of the dairy cows under study, plasma total protein, albumin, globulin, urea and Glucose did not show significant changes either either either between farms or in response to lactation stages. However, high levels of Globulins might indicate inflammation due to some diseases such as mastitis, metritis and lameness. Plasma level of Calcium and Phosphorous did not change significantly either between farms or due to stages of lactation.(Author) 129 refs. , 12 tabs.

Quantitative determination of amitriptyline and its metabolite in rat plasma by liquid chromatography-tandem mass spectrometry

Energy Technology Data Exchange (ETDEWEB)

Chae, Jungwoo; Baek, Inhwan; An, Junghwa; Kim, Eun Jung; Kwon, Kwangil [Chungnam National Univ., Daejeon (Korea, Republic of)

2012-07-15

A rapid, specific, and reliable LC-MS/MS-based bioanalytical method was developed and validated in rat plasma for the simultaneous quantitation of amitriptyline and its metabolite nortriptyline. Chromatographic separation of these analytes was achieved on a Gemini C18 column (50 X 4.60 mm, 5 {mu}m) using reversed-phase chromatography. The mobile phase was an isocratic solvent system consisting of 1% formic acid in water and methanol (10:90, v/v), at a flow rate of 0.2 mL/min. The analytical range was set as 0.1-500 ng/mL for amitriptyline and 0.08-500 ng/mL for nortriptyline using a 200 {mu}L plasma sample. The accuracy and precision of the assay were in accordance with FDA regulations for the validation of bioanalytical methods. The validated method was successfully applied to a pharmacokinetic study in six rats after oral administration of amitriptyline (15 mg/kg). This method allows laboratory scientists to rapidly determine amitriptyline and nortriptyline concentrations in plasma.

Simultaneous determination of sibutramine and its active metabolites in human plasma by LC-MS/MS and its application to a pharmacokinetic study.

Science.gov (United States)

Bae, Jung-Woo; Choi, Chang-Ik; Jang, Choon-Gon; Lee, Seok-Yong

2011-11-01

A simple and sensitive liquid chromatography-electrospray ionization-tandem mass spectrometry (LC-ESI-MS/MS) technique was developed and validated for the determination of sibutramine and its N-desmethyl metabolites (M1 and M2) in human plasma. After extraction with methyl t-butyl ether, chromatographic separation of analytes in human plasma was performed using a reverse-phase Luna C18 column with a mobile phase of acetonitrile-10 mm ammonium formate buffer (50:50, v/v) and quantified by ESI-MS/MS detection in positive ion mode. The flow rate of the mobile phase was 200 μL/min and the retention times of sibutramine, M1, M2 and internal standard (chlorpheniramine) were 1.5, 1.4, 1.3 and 0.9 min, respectively. The calibration curves were linear over the range 0.05-20 ng/mL, for sibutramine, M1 and M2. The lower limit of quantification was 0.05 ng/mL using 500 μL of human plasma. The mean accuracy and the precision in the intra- and inter-day validation for sibutramine, M1 and M2 were acceptable. This LC-MS/MS method showed improved sensitivity and a short run time for the quantification of sibutramine and its two active metabolites in plasma. The validated method was successfully applied to a pharmacokinetic study in human. Copyright © 2011 John Wiley & Sons, Ltd.

Plasma levels of artesunate and dihydroartemisinin in children with Plasmodium falciparum malaria in Gabon after administration of 50-milligram artesunate suppositories.

Science.gov (United States)

Halpaap, B; Ndjave, M; Paris, M; Benakis, A; Kremsner, P G

1998-03-01

A thermostable suppository of artesunate (artesunic acid) has been developed. In Gabon, 12 children with Plasmodium falciparum malaria received two administrations of this suppository in a 4-hr interval. Parasitemia and fever were then measured and the plasma levels of artesunate and its active metabolite, dihydroartemisinin, were determined by means of a reversed phase high-pressure liquid chromatography method using reductive electrochemical detection. Substantial parasite clearance (97-100%) was noted 24 hr after the beginning of the treatment and body temperature had returned to normal. Absorption, metabolism, and elimination of artesunate were rapid. Mean values of maximum plasma levels (Cmax) and maximum concentration peak times (tmax) were evaluated. The Cmax of dihydroartemisinin (0.18 +/- 0.10 microg/ml [mean +/- SE]) was higher than the Cmax of artesunate (0.09 +/- 0.04 microg/ml) and the tmax of dihydroartemisinin (1.13 +/- 0.58 hr) was higher than the tmax of artesunate (0.58 +/- 0.19 hr). Plasma levels 30 min after the second suppository administration were not consistently higher than those found 30 min after the first administration.

Metabolite characterization of a novel sedative drug, remimazolam in human plasma and urine using ultra high-performance liquid chromatography coupled with synapt high-definition mass spectrometry.

Science.gov (United States)

Zhou, Ying; Hu, Pei; Jiang, Ji

2017-04-15

Remimazolam is a new chemical entity belonging to the benzodiazepine class of sedative drugs, which shows faster-acting onset and recovery than currently available short-acting sedatives. In the present study, ultra high performance liquid chromatography with synapt high-definition mass spectrometry method combined with MassLynx software was established to characterize metabolites of remimazolam in human plasma and urine. In total, 5 human metabolites were detected, including 3 phase I and 2 phase II metabolites. There was no novel human metabolite detected compared to that in rat. Hydrolysis, glucuronidation and oxidation were the major metabolic reactions. To our knowledge, this is the first report of the human metabolic profile of remimazolam. Copyright © 2017 Elsevier B.V. All rights reserved.

Bioanalysis of a panel of neurotransmitters and their metabolites in plasma samples obtained from pediatric patients with neuroblastoma and Wilms' tumor.

Science.gov (United States)

Konieczna, Lucyna; Roszkowska, Anna; Stachowicz-Stencel, Teresa; Synakiewicz, Anna; Bączek, Tomasz

2018-02-01

This paper details the quantitative analysis of neurotransmitters, including dopamine (DA), norepinephrine (NE), epinephrine (E), and serotonin (5-HT), along with their respective precursors and metabolites in children with solid tumors: Wilms' tumor (WT) and neuroblastoma (NB). A panel of neurotransmitters was determined with the use of dispersive liquid-liquid microextraction (DLLME) technique combined with liquid-chromatography mass spectrometry (LC-MS/MS) in plasma samples obtained from a group of pediatric subjects with solid tumors and a control group of healthy children. Next, statistical univariate analysis (t-test) and multivariate analysis (Principal Component Analysis) were performed using chromatographic data. The levels of tyrosine (Tyr) and tryptophan (Trp) (the precursors of analyzed neurotransmitters) as well as 3,4-dihydroxyphenylacetic acid (DOPAC) (a product of metabolism of DA) were significantly higher in the plasma samples obtained from pediatric patients with WT than in the samples taken from the control group. Moreover, statistically significant differences were observed between the levels of 5-HT and homovanillic acid (HVA) in the plasma samples from pediatric patients with solid tumors and the control group. However, elevated levels of these analytes did not facilitate a clear distinction between pediatric patients with WT and those with NB. Nonetheless, the application of advanced statistical tools allowed the healthy controls to be differentiated from the pediatric oncological patients. The identification and quantification of a panel of neurotransmitters as potential prognostic factors in selected childhood malignancies may provide clinically relevant information about ongoing metabolic alterations, and it could potentially serve as an adjunctive strategy in the effective diagnosis and treatment of solid tumors in children. Copyright © 2017 Elsevier B.V. All rights reserved.

The human plasma-metabolome: Reference values in 800 French healthy volunteers; impact of cholesterol, gender and age.

Science.gov (United States)

Trabado, Séverine; Al-Salameh, Abdallah; Croixmarie, Vincent; Masson, Perrine; Corruble, Emmanuelle; Fève, Bruno; Colle, Romain; Ripoll, Laurent; Walther, Bernard; Boursier-Neyret, Claire; Werner, Erwan; Becquemont, Laurent; Chanson, Philippe

2017-01-01

Metabolomic approaches are increasingly used to identify new disease biomarkers, yet normal values of many plasma metabolites remain poorly defined. The aim of this study was to define the "normal" metabolome in healthy volunteers. We included 800 French volunteers aged between 18 and 86, equally distributed according to sex, free of any medication and considered healthy on the basis of their medical history, clinical examination and standard laboratory tests. We quantified 185 plasma metabolites, including amino acids, biogenic amines, acylcarnitines, phosphatidylcholines, sphingomyelins and hexose, using tandem mass spectrometry with the Biocrates AbsoluteIDQ p180 kit. Principal components analysis was applied to identify the main factors responsible for metabolome variability and orthogonal projection to latent structures analysis was employed to confirm the observed patterns and identify pattern-related metabolites. We established a plasma metabolite reference dataset for 144/185 metabolites. Total blood cholesterol, gender and age were identified as the principal factors explaining metabolome variability. High total blood cholesterol levels were associated with higher plasma sphingomyelins and phosphatidylcholines concentrations. Compared to women, men had higher concentrations of creatinine, branched-chain amino acids and lysophosphatidylcholines, and lower concentrations of sphingomyelins and phosphatidylcholines. Elderly healthy subjects had higher sphingomyelins and phosphatidylcholines plasma levels than young subjects. We established reference human metabolome values in a large and well-defined population of French healthy volunteers. This study provides an essential baseline for defining the "normal" metabolome and its main sources of variation.

Quantitation of anacetrapib, stable-isotope labeled-anacetrapib (microdose), and four metabolites in human plasma using liquid chromatography tandem mass spectrometry.

Science.gov (United States)

Chavez-Eng, C M; Lutz, R W; Li, H; Goykhman, D; Bateman, K P; Woolf, E

2016-02-01

An ultra-high performance liquid chromatography/tandem mass spectrometry (UPLC-MS/MS) method for the simultaneous determination of (4S,5R)-5-[3,5-bis (trifluoromethyl)phenyl]-3-{[4'-fluoro-5'-isopropyl-2'-methoxy-4-(trifluoromethyl)biphenyl-2-yl] methyl}-4-methyl-1,3-oxazolidin-2-one (anacetrapib, I) and [(13)C5(15)N]-anacetrapib, II in human plasma has been developed to support a clinical study to determine the absolute bioavailability of I. The analytes and the stable-isotope labeled internal standard ([(13)C7(15)N(2)H7]-anacetrapib, III) were extracted from 100μL of human plasma by liquid-liquid extraction using 20/80 isopropyl alcohol/hexane (v/v). The chromatographic separation of the analytes was achieved using Waters BEH Shield RP 18 (50×2.1mm×1.7μm) column and mobile phase gradient of 0.1% formic acid in water (Solvent A) and 0.1% formic acid in acetonitrile (Solvent B) at 0.6mL/min flow rate. The MS/MS detection was performed on AB Sciex 5000 or AB 5500 in positive electrospray ionization mode, operated in selected reaction monitoring mode. The assay was validated in the concentration range 1-2000ng/mL for I; and a lower curve range, 0.025-50ng/mL for II. In addition to the absolute bioavailability determination, it was desired to better elucidate the pharmacokinetic behavior of several hydroxylated metabolites of I. Toward this end, two exploratory assays for the hydroxy metabolites of I were qualified in the concentration range 0.5-500ng/mL. All metabolites were separated on a Supelco Ascentis Express Phenyl-Hexyl (50×2.1mm, 2.7μm) column. Metabolite M4 was analyzed in the negative mode with a mobile phase consisting of a gradient mixture of water (A) and acetonitrile (B). The other three metabolites, M1-M3 were analyzed in the positive mode using a mobile phase gradient of water with 0.1% formic acid (A) and acetonitrile with 0.1% formic acid (B). The assays were utilized to support a clinical study in which a microdosing approach was used to

Non-invasive assessment of glucocorticoid and androgen metabolite levels in cooperatively breeding Damaraland mole-rats (Fukomys damarensis).

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Medger, Katarina; Bennett, Nigel C; Lutermann, Heike; Ganswindt, Andre

2018-05-18

Dominant females of cooperative breeding species often use aggression to suppress reproduction of subordinate females, resulting in subordinates experiencing stress-related increases in glucocorticoid levels, which may cause reproductive down-regulation. This would suggest a general pattern with higher glucocorticoid levels in subordinate compared to dominant individuals; however, the opposite was found in a number of cooperatively breeding species. Furthermore, breeding females of the cooperatively breeding Damaraland mole-rats (Fukomys damarensis) exhibit very high androgen concentrations during the wet season, presumably to support their breeding monopoly. Hormone analysis in Damaraland mole-rats have typically been measured using plasma and urine, but faecal analysis offers additional advantages especially for field studies on this species. The present study examines the suitability of Damaraland mole-rat faecal samples for determining glucocorticoid metabolite (fGCM) and androgen metabolite (fAM) concentrations using enzyme immunoassays. Using these assays, we further evaluated the effects of breeding status on fGCM and fAM concentrations in wild-caught and captive Damaraland mole-rats. Wild-caught breeding and non-breeding males and females exhibited no differences in fAM concentrations. Immunoreactive fGCM concentrations were only high in male breeders and comparatively low in non-breeders and breeding females. Concentrations of fAMs and fGCMs were similar in captive males and females, but fAM concentrations were elevated in captive compared to wild-caught individuals, which may be related to a higher reproductive activity due to removal from the breeding female. The relatively uniform fAM and fGCM concentrations found in wild-caught mole-rats may be explained by a stable colony structure during the dry season during which this study was conducted. Limited dispersal opportunities result in lower aggression and stress levels within a colony and as a result

Analysis of human plasma metabolites across different liquid chromatography/mass spectrometry platforms: Cross-platform transferable chemical signatures.

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Telu, Kelly H; Yan, Xinjian; Wallace, William E; Stein, Stephen E; Simón-Manso, Yamil

2016-03-15

The metabolite profiling of a NIST plasma Standard Reference Material (SRM 1950) on different liquid chromatography/mass spectrometry (LC/MS) platforms showed significant differences. Although these findings suggest caution when interpreting metabolomics results, the degree of overlap of both profiles allowed us to use tandem mass spectral libraries of recurrent spectra to evaluate to what extent these results are transferable across platforms and to develop cross-platform chemical signatures. Non-targeted global metabolite profiles of SRM 1950 were obtained on different LC/MS platforms using reversed-phase chromatography and different chromatographic scales (conventional HPLC, UHPLC and nanoLC). The data processing and the metabolite differential analysis were carried out using publically available (XCMS), proprietary (Mass Profiler Professional) and in-house software (NIST pipeline). Repeatability and intermediate precision showed that the non-targeted SRM 1950 profiling was highly reproducible when working on the same platform (relative standard deviation (RSD) HPLC, UHPLC and nanoLC) on the same platform. A substantial degree of overlap (common molecular features) was also found. A procedure to generate consistent chemical signatures using tandem mass spectral libraries of recurrent spectra is proposed. Different platforms rendered significantly different metabolite profiles, but the results were highly reproducible when working within one platform. Tandem mass spectral libraries of recurrent spectra are proposed to evaluate the degree of transferability of chemical signatures generated on different platforms. Chemical signatures based on our procedure are most likely cross-platform transferable. Published in 2016. This article is a U.S. Government work and is in the public domain in the USA.

Detecting Beer Intake by Unique Metabolite Patterns.

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Gürdeniz, Gözde; Jensen, Morten Georg; Meier, Sebastian; Bech, Lene; Lund, Erik; Dragsted, Lars Ove

2016-12-02

Evaluation of the health related effects of beer intake is hampered by the lack of accurate tools for assessing intakes (biomarkers). Therefore, we identified plasma and urine metabolites associated with recent beer intake by untargeted metabolomics and established a characteristic metabolite pattern representing raw materials and beer production as a qualitative biomarker of beer intake. In a randomized, crossover, single-blinded meal study (MSt1), 18 participants were given, one at a time, four different test beverages: strong, regular, and nonalcoholic beers and a soft drink. Four participants were assigned to have two additional beers (MSt2). In addition to plasma and urine samples, test beverages, wort, and hops extract were analyzed by UPLC-QTOF. A unique metabolite pattern reflecting beer metabolome, including metabolites derived from beer raw material (i.e., N-methyl tyramine sulfate and the sum of iso-α-acids and tricyclohumols) and the production process (i.e., pyro-glutamyl proline and 2-ethyl malate), was selected to establish a compliance biomarker model for detection of beer intake based on MSt1. The model predicted the MSt2 samples collected before and up to 12 h after beer intake correctly (AUC = 1). A biomarker model including four metabolites representing both beer raw materials and production steps provided a specific and accurate tool for measurement of beer consumption.

The issue of HPLC determination of endogenous lipoic acid in human plasma.

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Sechovcová, Soňa; Královcová, Pavla; Kanďár, Roman; Ventura, Karel

2018-05-01

Lipoic acid (LA) is used extensively as a therapeutic agent for the treatment of various diseases. Many methods have been reported for the determination of LA plasma levels and its metabolites after its supplementation, but available information concerning endogenous plasma levels is still scarce. Studies which directly focused on determining the endogenous plasma levels provided highly controversial results, endogenous plasma levels of LA: 2.4 and 4.9 nmol/L respectively. However, the levels of free LA in the plasma of nonsupplemented voluntary blood donors were not detectable in all cases. The presented results of our study show that endogenous concentrations of LA are <1.85 nmol/L. Copyright © 2017 John Wiley & Sons, Ltd.

Fasting and exercise increase plasma cannabinoid levels in THC pre-treated rats: an examination of behavioural consequences.

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Wong, Alexander; Keats, Kirily; Rooney, Kieron; Hicks, Callum; Allsop, David J; Arnold, Jonathon C; McGregor, Iain S

2014-10-01

Δ(9)-Tetrahydrocannabinol (THC), the main psychoactive constituent of cannabis, accumulates in fat tissue where it can remain for prolonged periods. Under conditions of increased fat utilisation, blood cannabinoid concentrations can increase. However, it is unclear whether this has behavioural consequences. Here, we examined whether rats pre-treated with multiple or single doses of THC followed by a washout would show elevated plasma cannabinoids and altered behaviour following fasting or exercise manipulations designed to increase fat utilisation. Behavioural impairment was measured as an inhibition of spontaneous locomotor activity or a failure to successfully complete a treadmill exercise session. Fat utilisation was indexed by plasma free fatty acid (FFA) levels with plasma concentrations of THC and its terminal metabolite (-)-11-nor-9-carboxy-∆(9)-tetrahydrocannabinol (THC-COOH) also measured. Rats given daily THC (10 mg/kg) for 5 days followed by a 4-day washout showed elevated plasma THC-COOH when fasted for 24 h relative to non-fasted controls. Fasted rats showed lower locomotor activity than controls suggesting a behavioural effect of fat-released THC. However, rats fasted for 20 h after a single 5-mg/kg THC injection did not show locomotor suppression, despite modestly elevated plasma THC-COOH. Rats pre-treated with THC (5 mg/kg) and exercised 20 h later also showed elevated plasma THC-COOH but did not differ from controls in their likelihood of completing 30 min of treadmill exercise. These results confirm that fasting and exercise can increase plasma cannabinoid levels. Behavioural consequences are more clearly observed with pre-treatment regimes involving repeated rather than single THC dosing.

Impacts of rising tropospheric ozone on photosynthesis and metabolite levels on field grown soybean.

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Sun, Jindong; Feng, Zhaozhong; Ort, Donald R

2014-09-01

The response of leaf photosynthesis and metabolite profiles to ozone (O3) exposure ranging from 37 to 116 ppb was investigated in two soybean cultivars Dwight and IA3010 in the field under fully open-air conditions. Leaf photosynthesis, total non-structural carbohydrates (TNC) and total free amino acids (TAA) decreased linearly with increasing O3 levels in both cultivars with average decrease of 7% for an increase in O3 levels by 10 ppb. Ozone interacted with developmental stages and leaf ages, and caused higher damage at later reproductive stages and in older leaves. Ozone affected yield mainly via reduction of maximum rate of Rubisco carboxylation (Vcmax) and maximum rates of electron transport (Jmax) as well as a shorter growing season due to earlier onset of canopy senescence. For all parameters investigated the critical O3 levels (∼50 ppb) for detectable damage fell within O3 levels that occur routinely in soybean fields across the US and elsewhere in the world. Strong correlations were observed in O3-induced changes among yield, photosynthesis, TNC, TAA and many metabolites. The broad range of metabolites that showed O3 dose dependent effect is consistent with multiple interaction loci and thus multiple targets for improving the tolerance of soybean to O3. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Inter- and intra-individual variability in the levels of plasma homovanillic acid in schizophrenic patients.

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Zumárraga, Mercedes; Dávila, Ricardo; González-Torres, Miguel Angel; Anguiano, Juan B; Zabalo, María José; Basterreche, Nieves; Arrúe, Aurora; Zamalloa, María Isabel; Guimón, José

2007-04-13

Changes in the levels of homovanillic acid in blood plasma (pHVA) may reflect changes which occur in the brain. In healthy individuals, this concentration of pHVA is stable over time. Over the course of one month, we studied 98 acute schizophrenic patients who had not been taking any medication but were administered neuroleptics upon hospital admission, together with 23 chronic schizophrenic patients on long-term treatment from whom medication was withdrawn. Blood samples were taken at regular intervals from each individual and the concentration of plasma homovanillic acid was measured. We found relative stable values of pHVA with an intraclass correlation coefficient of 0.363 in acute patients and 0.638 (ppHVA and the presence of pharmacological stimuli, we found a certain reproducibility in the levels of this dopamine metabolite. These findings are consistent with the idea that the dopaminergic activity is characterized by a constitutive value which would be under genetic control. The higher stability observed in chronic patients may reflect a weaker, age-related dopaminergic plasticity; conversely, it may indicate that a lack of plasticity in response to a pharmacological stimulus may be an indicator of poorer prognosis.

Fat oxidation, hormonal and plasma metabolite kinetics during a submaximal incremental test in lean and obese adults.

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Lanzi, Stefano; Codecasa, Franco; Cornacchia, Mauro; Maestrini, Sabrina; Salvadori, Alberto; Brunani, Amelia; Malatesta, Davide

2014-01-01

This study aimed to compare fat oxidation, hormonal and plasma metabolite kinetics during exercise in lean (L) and obese (O) men. Sixteen L and 16 O men [Body Mass Index (BMI): 22.9 ± 0.3 and 39.0 ± 1.4 kg · m(-2)] performed a submaximal incremental test (Incr) on a cycle-ergometer. Fat oxidation rates (FORs) were determined using indirect calorimetry. A sinusoidal model, including 3 independent variables (dilatation, symmetry, translation), was used to describe fat oxidation kinetics and determine the intensity (Fat(max)) eliciting maximal fat oxidation. Blood samples were drawn for the hormonal and plasma metabolite determination at each step of Incr. FORs (mg · FFM(-1) · min(-1)) were significantly higher from 20 to 30% of peak oxygen uptake (VO2peak) in O than in L and from 65 to 85% VO2peak in L than in O (p ≤ 0.05). FORs were similar in O and in L from 35 to 60% VO2peak. Fat max was 17% significantly lower in O than in L (poxidation kinetics were characterized by similar translation, significantly lower dilatation and left-shift symmetry in O compared with L (poxidation at high exercise intensities suggest that the difference in the fat oxidation kinetics is likely linked to impaired muscular capacity to oxidize NEFA in O. These results may have important implications for the appropriate exercise intensity prescription in training programs designed to optimize fat oxidation in O.

Methodological considerations for measuring glucocorticoid metabolites in feathers

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Berk, Sara A.; McGettrick, Julie R.; Hansen, Warren K.; Breuner, Creagh W.

2016-01-01

In recent years, researchers have begun to use corticosteroid metabolites in feathers (fCORT) as a metric of stress physiology in birds. However, there remain substantial questions about how to measure fCORT most accurately. Notably, small samples contain artificially high amounts of fCORT per millimetre of feather (the small sample artefact). Furthermore, it appears that fCORT is correlated with circulating plasma corticosterone only when levels are artificially elevated by the use of corticosterone implants. Here, we used several approaches to address current methodological issues with the measurement of fCORT. First, we verified that the small sample artefact exists across species and feather types. Second, we attempted to correct for this effect by increasing the amount of methanol relative to the amount of feather during extraction. We consistently detected more fCORT per millimetre or per milligram of feather in small samples than in large samples even when we adjusted methanol:feather concentrations. We also used high-performance liquid chromatography to identify hormone metabolites present in feathers and measured the reactivity of these metabolites against the most commonly used antibody for measuring fCORT. We verified that our antibody is mainly identifying corticosterone (CORT) in feathers, but other metabolites have significant cross-reactivity. Lastly, we measured faecal glucocorticoid metabolites in house sparrows and correlated these measurements with corticosteroid metabolites deposited in concurrently grown feathers; we found no correlation between faecal glucocorticoid metabolites and fCORT. We suggest that researchers should be cautious in their interpretation of fCORT in wild birds and should seek alternative validation methods to examine species-specific relationships between environmental challenges and fCORT. PMID:27335650

Feeding motivation and plasma metabolites in pregnant sows fed diets rich in dietary fiber either once or twice daily.

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Jensen, M B; Pedersen, L J; Theil, P K; Yde, C C; Bach Knudsen, K E

2012-06-01

The present study investigated the effects of source and level of dietary fiber (DF) and feeding frequency (once vs. twice daily) on feeding motivation and plasma metabolites at 4 different time points post feeding. Sixty pregnant sows (Sus scrofa, 4 blocks of 15 sows) were allocated to 1 of 5 diets within blocks. Four diets were restricted (approximately 35 MJ ME/d): a barley and wheat control diet (171 g DF/kg DM; 12 g DF/MJ ME), and 3 fiber diets formulated to contain 35% DF by including pectin residue (323 g DF/kg DM; 25 g DF/MJ ME), potato pulp (404 g DF/kg DM; 29 g DF/MJ ME), or sugar beet pulp (367 g DF/kg DM; 25 g DF/MJ ME). The fifth diet was a mixture including an equal amount of the 3 fiber diets offered semi ad libitum (ad libitum access to feed during 6 periods of 1 h starting at 0300, 0600, 1100, 1500, 1800, and 2300; 354 g DF/kg DM; 25 g DF/MJ ME). The experimental period included 2 periods of 4 wk each. Restricted-fed sows were fed once daily (0800 h) during the first period and twice daily (0800 and 1500 h) during the second period, or vice versa. Semi ad libitum fed sows had access to feed 6 times a day in both periods. In each period, the feeding motivation was assessed in an operant conditioning test, and samples of peripheral blood were taken in a balanced design, at 0900, 1200, 1900, and 0700 h, corresponding to 1, 4, 11, and 23 h after feeding for restricted sows fed once daily. No differences in the feeding motivation were found between the 4 restricted diets at any of the time points post feeding, but semi ad libitum fed sows had a decreased feeding motivation (P motivation at 1900 h (P motivation during the night compared with feeding once daily. Among restricted-fed sows, plasma concentrations of short-chain fatty acids (SCFA) were greater in sows fed high-fiber diets compared with the control (P = 0.02). Nonesterified fatty acid was least in sows on the control diet and greatest in sows on the potato diet, whereas sows on the pectin and

Usefulness of saliva for measurement of 3,4-methylenedioxymethamphetamine and its metabolites: correlation with plasma drug concentrations and effect of salivary pH.

Science.gov (United States)

Navarro, M; Pichini, S; Farré, M; Ortuño, J; Roset, P N; Segura, J; de la Torre, R

2001-10-01

Saliva is an alternative biologic matrix for drugs-of-abuse testing that offers the advantages of noninvasive, rapid, and easy sampling. We studied the excretion profile of 3,4-methylenedioxymethamphetamine (MDMA) and its metabolites in both saliva and plasma, as well the effect of the drug on salivary pH. Saliva and plasma samples were obtained from eight healthy MDMA consumers after ingestion of a single 100-mg dose of the drug. Concentrations of MDMA and its main metabolites, 3,4-methylenedioxyamphetamine (MDA) and 4-hydroxy-3-methoxymethamphetamine (HMMA), in saliva and plasma were measured by gas chromatography-mass spectrometry. Apparent pharmacokinetic parameters for MDMA in saliva were estimated, and the saliva-to-plasma ratio at each time interval was calculated and correlated with salivary pH. MDMA, MDA, and HMMA were detected in saliva. Salivary concentrations of MDMA were 1728.9-6510.6 microg/L and peaked at 1.5 h after drug intake. This was followed by a progressive decrease, with a mean concentration of 126.2 microg/L at 24 h. The saliva-to-plasma ratio was 32.3-1.2, with a peak of 18.1 at 1.5 h after drug administration. Salivary pH seemed to be affected by MDMA administration; pH values decreased by 0.6 units (mean pH values of 6.9 and 6.8 at 1.5 and 4 h after drug administration vs predose pH of 7.4). Measurement of MDMA in saliva is a valuable alternative to determination of plasma drug concentrations in both clinical and toxicologic studies. On-site testing is also facilitated by noninvasive and rapid collection of salivary specimens.

Reference range levels of polycyclic aromatic hydrocarbons in the US population by measurement of urinary monohydroxy metabolites

International Nuclear Information System (INIS)

Grainger, James; Huang, Wenlin; Patterson, Donald G.; Turner, Wayman E.; Pirkle, James; Caudill, Samuel P.; Wang, Richard Y.; Needham, Larry L.; Sampson, Eric J.

2006-01-01

We developed a gas chromatography isotope-dilution high-resolution mass spectrometry (GC/Id-HRMS) method for measuring 14 polycyclic aromatic hydrocarbon (PAH) metabolites representing seven parent PAHs in 3 mL of urine at low parts-per-trillion levels. PAH levels were determined in urine samples collected in 1999 and 2000 from approximately 2400 participants in the National Health and Nutrition Examination Survey, and, for the first time, reference range values were calculated for these metabolites in the US population. Using this GC/ID-HRMS method, we found detectable concentrations for monohydroxy metabolite isomers of fluorene, phenanthrene, fluoranthene, pyrene, and chrysene, benzo[c]phenanthrene, and benz[a]anthracene. Some monohydroxy metabolite isomers of benzo[c]phenanthrene, chrysene, and benz[a]anthracene exhibited low detection frequencies that did not allow for geometric mean calculations. Our study results enabled us to establish a reference range for the targeted PAHs in the general US population

Human Plasma Metabolomics Study across All Stages of Age-Related Macular Degeneration Identifies Potential Lipid Biomarkers.

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Laíns, Inês; Kelly, Rachel S; Miller, John B; Silva, Rufino; Vavvas, Demetrios G; Kim, Ivana K; Murta, Joaquim N; Lasky-Su, Jessica; Miller, Joan W; Husain, Deeba

2018-02-01

To characterize the plasma metabolomic profile of patients with age-related macular degeneration (AMD) using mass spectrometry (MS). Cross-sectional observational study. We prospectively recruited participants with a diagnosis of AMD and a control group (>50 years of age) without any vitreoretinal disease. All participants underwent color fundus photography, used for AMD diagnosis and staging, according to the Age-Related Eye Disease Study classification scheme. Fasting blood samples were collected and plasma was analyzed by Metabolon, Inc. (Durham, NC), using ultrahigh-performance liquid chromatography (UPLC) and high-resolution MS. Metabolon's hardware and software were used to identify peaks and control quality. Principal component analysis and multivariate regression were performed to assess differences in the metabolomic profiles of AMD patients versus controls, while controlling for potential confounders. For biological interpretation, pathway enrichment analysis of significant metabolites was performed using MetaboAnalyst. The primary outcome measures were levels of plasma metabolites in participants with AMD compared with controls and among different AMD severity stages. We included 90 participants with AMD (30 with early AMD, 30 with intermediate AMD, and 30 with late AMD) and 30 controls. Using UPLC and MS, 878 biochemicals were identified. Multivariate logistic regression identified 87 metabolites with levels that differed significantly between AMD patients and controls. Most of these metabolites (82.8%; n = 72), including the most significant metabolites, belonged to the lipid pathways. Analysis of variance revealed that of the 87 metabolites, 48 (55.2%) also were significantly different across the different stages of AMD. A significant enrichment of the glycerophospholipids pathway was identified (P = 4.7 × 10 -9 ) among these metabolites. Participants with AMD have altered plasma metabolomic profiles compared with controls. Our data suggest

Correlative analysis of metabolite profiling of Danggui Buxue Tang in rat biological fluids by rapid resolution LC-TOF/MS.

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Li, Chang-Yin; Qi, Lian-Wen; Li, Ping

2011-04-28

In this work, the metabolite profiles of Danggui Buxue Tang (DBT) in rat bile and plasma were qualitatively described, and the possible metabolic pathways of DBT were subsequently proposed. Emphasis was put on correlative analysis of metabolite profiling in different biological fluids. After oral administration of DBT, bile and plasma samples were collected and pretreated by solid phase extraction. Rapid resolution liquid chromatography coupled to time-of-flight mass spectrometry (RRLC-TOFMS) was used for characterization of DBT-related compounds (parent compounds and metabolites) in biological matrices. A total of 142 metabolites were detected and tentatively identified from the drug-containing bile and plasma samples. Metabolite profiling shows that rat bile contained relatively more glutathione-derived conjugates, more saponins compounds and more diverse forms of metabolites than urine. The metabolite profile in plasma revealed that glucuronide conjugates of isoflavonoids, dimmers, acetylcysteine conjugates and parent form of phthalides, as well as saponin aglycones were the major circulating forms of DBT. Collectively, the metabolite profile analysis of DBT in different biological matrices provided a comprehensive understanding of the in vivo metabolic fates of constituents in DBT. Copyright © 2011 Elsevier B.V. All rights reserved.

Different levels of UV-B resistance in Vaccinium corymbosum cultivars reveal distinct backgrounds of phenylpropanoid metabolites.

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Luengo Escobar, Ana; Magnum de Oliveira Silva, Franklin; Acevedo, Patricio; Nunes-Nesi, Adriano; Alberdi, Miren; Reyes-Díaz, Marjorie

2017-09-01

UV-B radiation induces several physiological and biochemical effects that can influence regulatory plant processes. Vaccinium corymbosum responds differently to UV-B radiation depending on the UV-B resistance of cultivars, according to their physiological and biochemical features. In this work, the effect of two levels of UV-B radiation during long-term exposure on the phenylpropanoid biosynthesis, and the expression of genes associated with flavonoid biosynthesis as well as the absolute quantification of secondary metabolites were studied in two contrasting UV-B-resistant cultivars (Legacy, resistant and Bluegold, sensitive). Multivariate analyses were performed to understand the role of phenylpropanoids in UV-B defense mechanisms. The amount of phenylpropanoid compounds was generally higher in Legacy than in Bluegold. Different expression levels of flavonoid biosynthetic genes for both cultivars were transiently induced, showing that even in longer period of UV-B exposure; plants are still adjusting their phenylpropanoids at the transcription levels. Multivariate analysis in Legacy indicated no significant correlation between gene expression and the levels of the flavonoids and phenolic acids. By contrast, in the Bluegold cultivar higher number of correlations between secondary metabolite and transcript levels was found. Taken together, the results indicated different adjustments between the cultivars for a successful UV-B acclimation. While the sensitive cultivar depends on metabolite adjustments to respond to UV-B exposure, the resistant cultivar also possesses an intrinsically higher antioxidant and UV-B screening capacity. Thus, we conclude that UV-B resistance involves not only metabolite level adjustments during the acclimation period, but also depends on the intrinsic metabolic status of the plant and metabolic features of the phenylpropanoid compounds. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

Determination of ketamine and its main metabolites by liquid chromatography coupled to tandem mass spectrometry in pig plasma: Comparison of extraction methods.

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Ramiole, Cindy; D'Hayer, Benoit; Boudy, Vincent; Legagneux, Josette; Fonsart, Julien; Houzé, Pascal

2017-11-30

A rapid, sensitive and specific liquid chromatography coupled to tandem mass spectrometry method was developed for the simultaneous quantification pig plasma of ketamine and its two principal metabolites, norketamine and dehydronorketamine. Three extraction procoles were assessed including acetonitrile precipitation, Oase™ microplate extraction, and liquid-liquid extraction. Oase™ microplate extraction induced no significant matrix effect, important signal/noise ratio and good recoveries, ranging from 82 to 87% for the considered compounds. Using this extraction procedure, the assay was linear in the dynamic range 10-3000ng/mL (R 2 >0.99) regardless of the analytes. Intra- and inter-day accuracies were less than 12% for all compounds and intra- and inter-day precisions expressed as RSD were within ketamine, norketamine and dehydronorketamine concentrations up to 15,000ng/mL can be determined with good precision using appropriate sample dilution. The assay was successfully applied to pig plasma samples to determine the pharmacokinetics of ketamine and the consecutive metabolites after buccal administration of a 4mg/kg ketamine base solutions. Copyright © 2017 Elsevier B.V. All rights reserved.

The metabolites in peripheral blood mononuclear cells showed greater differences between patients with impaired fasting glucose or type 2 diabetes and healthy controls than those in plasma.

Science.gov (United States)

Kim, Minjoo; Kim, Minkyung; Han, Ji Yun; Lee, Sang-Hyun; Jee, Sun Ha; Lee, Jong Ho

2017-03-01

To determine differences between peripheral blood mononuclear cells and the plasma metabolites in patients with impaired fasting glucose or type 2 diabetes and healthy controls. In all, 65 nononobese patients (aged 30-70 years) with impaired fasting glucose or type 2 diabetes and 65 nonobese sex-matched healthy controls were included, and fasting peripheral blood mononuclear cell and plasma metabolomes were profiled. The diabetic or impaired fasting glucose patients showed higher circulating and peripheral blood mononuclear cell lipoprotein phospholipase A 2 activities, high-sensitivity C-reactive protein and tumour necrosis factor-α than controls. Compared with controls, impaired fasting glucose or diabetic subjects showed increases in 11 peripheral blood mononuclear cell metabolites: six amino acids (valine, leucine, methionine, phenylalanine, tyrosine and tryptophan), l-pyroglutamic acid, two fatty acid amides containing palmitic amide and oleamide and two lysophosphatidylcholines. In impaired fasting glucose or diabetic patients, peripheral blood mononuclear cell lipoprotein phospholipase A 2 positively associated with peripheral blood mononuclear cell lysophosphatidylcholines and circulating inflammatory markers, including tumour necrosis factor-α, high-sensitivity C-reactive protein and lipoprotein phospholipase A 2 activities. In plasma metabolites between patients and healthy controls, we observed significant increases in only three amino acids (proline, valine and leucine) and decreases in only five lysophosphatidylcholines. This study demonstrates significant differences in the peripheral blood mononuclear cell metabolome in patients with impaired fasting glucose or diabetes compared with healthy controls. These differences were greater than those observed in the plasma metabolome. These data suggest peripheral blood mononuclear cells as a useful tool to better understand the inflammatory pathophysiology of diabetes.

Low plasma progranulin levels in children with autism

Directory of Open Access Journals (Sweden)

Mostafa Gehan A

2011-09-01

Full Text Available Abstract Background Autoimmunity to brain may play a pathogenic role in autism. In autoimmune disorders, the formation of antigen-antibody complexes triggers an inflammatory response by inducing the infiltration of neutrophils. Local administration of recombinant progranulin, which is an anti-inflammatory neurotrophic factor, potently inhibit neutrophilic inflammation in vivo, demonstrating that progranulin represents a crucial inflammation-suppressing mediator. We are the first to measure plasma progranulin levels in autism. Methods Plasma levels of progranulin were measured, by ELISA, in 40 autistic patients, aged between 3 and 12 years, and 40 healthy-matched children. Results Autistic children had significantly lower plasma progranulin levels, P = 0.001. Reduced plasma progranulin levels were found in 65% (26/40 of autistic children. On the other hand, there was a non significant difference between plasma progranulin levels of children with mild to moderate autism and patients with severe autism, P = 0.11. Conclusions Plasma progranulin levels were reduced in a subgroup of patients with autism. Progranulin insufficiency in some patients with autism may result in many years of reduced neutrotrophic support together with cumulative damage in association with dysregulated inflammation that may have a role in autism. However, these data should be treated with caution until further investigations are performed, with a larger subject population, to determine whether the decrease of plasma progranulin levels is a mere consequence of autism or has a pathogenic role in the disease. The role of progranulin therapy should also be studied in autism.

Low plasma progranulin levels in children with autism.

Science.gov (United States)

Al-Ayadhi, Laila Y; Mostafa, Gehan A

2011-09-05

Autoimmunity to brain may play a pathogenic role in autism. In autoimmune disorders, the formation of antigen-antibody complexes triggers an inflammatory response by inducing the infiltration of neutrophils. Local administration of recombinant progranulin, which is an anti-inflammatory neurotrophic factor, potently inhibit neutrophilic inflammation in vivo, demonstrating that progranulin represents a crucial inflammation-suppressing mediator. We are the first to measure plasma progranulin levels in autism. Plasma levels of progranulin were measured, by ELISA, in 40 autistic patients, aged between 3 and 12 years, and 40 healthy-matched children. Autistic children had significantly lower plasma progranulin levels, P = 0.001. Reduced plasma progranulin levels were found in 65% (26/40) of autistic children.On the other hand, there was a non significant difference between plasma progranulin levels of children with mild to moderate autism and patients with severe autism, P = 0.11. Plasma progranulin levels were reduced in a subgroup of patients with autism. Progranulin insufficiency in some patients with autism may result in many years of reduced neutrotrophic support together with cumulative damage in association with dysregulated inflammation that may have a role in autism. However, these data should be treated with caution until further investigations are performed, with a larger subject population, to determine whether the decrease of plasma progranulin levels is a mere consequence of autism or has a pathogenic role in the disease. The role of progranulin therapy should also be studied in autism.

Plasma concentrations of cortisol and PGF2α metabolite in Danish sows during mating, and intrauterine and conventional insemination

Directory of Open Access Journals (Sweden)

Kindahl Hans

2007-12-01

Full Text Available Abstract Background The aims of the present work was to study whether there are any relationships between cortisol and PG-metabolite in mated sows or inseminated with the intrauterine technique and compare these to changes occurring in conventionally inseminated sow. Methods Thirty three crossbred sows (Danish Landrace × Danish Large White were fitted with jugular vein catheters through vena auricularis from one of the ears. The sows were randomly divided into three groups (Boar-, IUI- and AI-group and blood samples were collected before, during and after service. In a final evaluation only 25 sows that became pregnant and farrowed piglets at full term were used. Results Cortisol concentrations increased in all groups but Boar-group (n = 8 had a significantly higher cortisol during 10 to 20 min after service than sows in AI-group (n = 8. In mated sows cortisol concentrations peaked at 15 minutes after service. The Boar-group (n = 8 showed no ascending PG-metabolite levels during the whole experiment, while both IUI- and AI-groups (n = 9 and n = 8, respectively had a 2.5-fold increase in PG-metabolite 15 minutes after service. Conclusion In conclusion, mating of sows by a boar results in a greater increase of cortisol than AI and without an elevation of PG-metabolite levels, which was seen in both the inseminated groups. It was also demonstrated that IUI-group had an earlier significant increase of PG-metabolite levels than sows inseminated conventionally. Further investigation using different semen extenders or even different type of insemination catheters might be helpful in understanding the reason for an immediate increase of PG-metabolite after insemination but not after mating.

Plasma concentrations of cortisol and PGF2α metabolite in Danish sows during mating, and intrauterine and conventional insemination

Science.gov (United States)

Norrby, Mattias; Madsen, Mads T; Alexandersen, Charlotte Borg; Kindahl, Hans; Madej, Andrzej

2007-01-01

Background The aims of the present work was to study whether there are any relationships between cortisol and PG-metabolite in mated sows or inseminated with the intrauterine technique and compare these to changes occurring in conventionally inseminated sow. Methods Thirty three crossbred sows (Danish Landrace × Danish Large White) were fitted with jugular vein catheters through vena auricularis from one of the ears. The sows were randomly divided into three groups (Boar-, IUI- and AI-group) and blood samples were collected before, during and after service. In a final evaluation only 25 sows that became pregnant and farrowed piglets at full term were used. Results Cortisol concentrations increased in all groups but Boar-group (n = 8) had a significantly higher cortisol during 10 to 20 min after service than sows in AI-group (n = 8). In mated sows cortisol concentrations peaked at 15 minutes after service. The Boar-group (n = 8) showed no ascending PG-metabolite levels during the whole experiment, while both IUI- and AI-groups (n = 9 and n = 8, respectively) had a 2.5-fold increase in PG-metabolite 15 minutes after service. Conclusion In conclusion, mating of sows by a boar results in a greater increase of cortisol than AI and without an elevation of PG-metabolite levels, which was seen in both the inseminated groups. It was also demonstrated that IUI-group had an earlier significant increase of PG-metabolite levels than sows inseminated conventionally. Further investigation using different semen extenders or even different type of insemination catheters might be helpful in understanding the reason for an immediate increase of PG-metabolite after insemination but not after mating. PMID:18053237

Plasma concentrations of cortisol and PGF2alpha metabolite in Danish sows during mating, and intrauterine and conventional insemination.

Science.gov (United States)

Norrby, Mattias; Madsen, Mads T; Alexandersen, Charlotte Borg; Kindahl, Hans; Madej, Andrzej

2007-12-05

The aims of the present work was to study whether there are any relationships between cortisol and PG-metabolite in mated sows or inseminated with the intrauterine technique and compare these to changes occurring in conventionally inseminated sow. Thirty three crossbred sows (Danish Landrace x Danish Large White) were fitted with jugular vein catheters through vena auricularis from one of the ears. The sows were randomly divided into three groups (Boar-, IUI- and AI-group) and blood samples were collected before, during and after service. In a final evaluation only 25 sows that became pregnant and farrowed piglets at full term were used. Cortisol concentrations increased in all groups but Boar-group (n = 8) had a significantly higher cortisol during 10 to 20 min after service than sows in AI-group (n = 8). In mated sows cortisol concentrations peaked at 15 minutes after service. The Boar-group (n = 8) showed no ascending PG-metabolite levels during the whole experiment, while both IUI- and AI-groups (n = 9 and n = 8, respectively) had a 2.5-fold increase in PG-metabolite 15 minutes after service. In conclusion, mating of sows by a boar results in a greater increase of cortisol than AI and without an elevation of PG-metabolite levels, which was seen in both the inseminated groups. It was also demonstrated that IUI-group had an earlier significant increase of PG-metabolite levels than sows inseminated conventionally. Further investigation using different semen extenders or even different type of insemination catheters might be helpful in understanding the reason for an immediate increase of PG-metabolite after insemination but not after mating.

Development and validation of an UHPLC-HRMS protocol for the analysis of flavan-3-ol metabolites and catabolites in urine, plasma and feces of rats fed a red wine proanthocyanidin extract.

Science.gov (United States)

Pereira-Caro, Gema; Ordóñez, José Luis; Ludwig, Iziar; Gaillet, Sylvie; Mena, Pedro; Del Rio, Daniele; Rouanet, Jean-Max; Bindon, Keren A; Moreno-Rojas, José Manuel; Crozier, Alan

2018-06-30

This study developed, optimized and validated an ultra-high-performance liquid chromatography-high-resolution mass spectrometry (UHPLC-HRMS) method to identify and quantify metabolites and microbial-derived catabolites in urine, plasma and feces of rats following ingestion of 50 mg of a red wine proanthocyanidin-rich extract. The method was validated for specificity, linearity, limit of detection (LD) and quantification (LQ), intra-day and inter-day precision, recovery and matrix effects, which were determined for 34 compounds in the three biological matrices. After method validation, three parent flavan-3-ols, four 5-carbon side chain ring fission metabolites, and 27 phenolic acid and aromatic catabolites were quantified in plasma, urine and feces after red wine proanthocyanidin intake. These results establish the value of the UHPLC-HRMS protocol in obtaining a detailed picture of proanthocyanidin metabolites and their microbial-derived catabolites, along with their phase II metabolites, in biological fluids of rat, and potentially in human clinical studies designed to evaluate the bioavailability of dietary flavan-3-ols. Copyright © 2018 Elsevier Ltd. All rights reserved.

Measurement of 12(S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid and its metabolite 12-oxo-5Z,8E,10E-heptadecatrienoic acid in human plasma by gas chromatography/negative ion chemical ionization mass spectrometry

International Nuclear Information System (INIS)

Hofmann, U.; Seefried, S.; Meese, C.O.; Mettang, T.; Huebel, E.K.; Kuhlmann, U.

1990-01-01

Thromboxane A2, the predominant product of arachidonic acid metabolism in the blood platelet, is a potent vasoconstrictor and platelet agonist. During its biosynthesis from cyclic endoperoxide, 12(S)-hydroxy-5Z,8E,10E-heptadecatrienoic acid (HHT) is formed in equal amounts. The further metabolism of HHT, catalyzed by 15-hydroxyprostaglandin dehydrogenase, leads to 12-oxo-5Z,8E,10E-heptadecatrienoic acid (Oxo-HT). Sample workup procedures are described which allow for the sensitive and reproducible determination of these two arachidonic acid metabolites in human plasma by gas chromatography-mass spectrometry in the presence of deuterated analogues as internal standards. HHT is derivatized to the pentafluorobenzyl ester tert-butyldimethylsilyl ether. In order to enable quantification of low concentrations of about 10 pg/ml in nonstimulated human plasma, the samples have to be purified by HPLC. Oxo-HT is derivatized to the pentafluorobenzyl ester, which is purified by HPLC, and then derivatized to the trimethylsilyloxime. The method allows quantification of Oxo-HT in concentrations down to 10 pg/ml plasma. The reported methods have been used to measure HHT and Oxo-HT in stimulated platelet rich plasma and to quantify HHT in nonstimulated plasma. Determination of endogenous levels of these two arachidonic acid metabolites may give new insights into the overall biosynthesis of thromboxane A2 in man

Simultaneous analysis of regorafenib and sorafenib and three of their metabolites in human plasma using LC-MS/MS.

Science.gov (United States)

Allard, Marie; Khoudour, Nihel; Rousseau, Benoît; Joly, Charlotte; Costentin, Charlotte; Blanchet, Benoît; Tournigand, Christophe; Hulin, Anne

2017-08-05

A new liquid chromatography-tandem mass spectrometry (LC-MS/MS) method, performed by electrospray ionization in positive mode using a triple quadrupole mass spectrometry, has been developed and validated for the simultaneous determination of regorafenib (REGO), its two metabolites regorafenib-M2 and regorafenib-M5, sorafenib (SORA), and its N-oxide metabolite in human plasma. Separation is achieved on an Hypersil Gold ® column using a gradient elution of 10mM ammonium formate containing 0.1% formic acid (A) and acetonitrile containing 0.1% formic acid (B) at a flow rate of 0.3mL/min. After addition of two internal standards and a protein precipitation, the supernatant is diluted two-fold in a 0.1% (v/v) formic acid solution. Two selected reaction monitoring transitions are used, for each analyte, one for quantitation and the second one for confirmation. The standard curves are ranged from 50 to 5 000ng/mL for REGO and its metabolites and 80 to 5 000ng/mL for SORA and its metabolite and were fitted to a 1/x weighted linear regression model. The method also showed satisfactory results in terms of sensitivity, specificity, precision (intra- and inter-day CV from 2.4 to 10.2%), accuracy (from 91.0 to 111.7%), recovery as well as stability of the analytes under various conditions. The method is usually used in clinical practice in order to improve the SORA treatment for renal carcinoma, REGO treatment for colorectal cancer and both for hepatocellular carcinoma. Copyright © 2017 Elsevier B.V. All rights reserved.

Determination of oxycodone and its major metabolites noroxycodone and oxymorphone by ultra-high-performance liquid chromatography tandem mass spectrometry in plasma and urine: application to real cases.

Science.gov (United States)

Pantano, Flaminia; Brauneis, Stefano; Forneris, Alexandre; Pacifici, Roberta; Marinelli, Enrico; Kyriakou, Chrystalla; Pichini, Simona; Busardò, Francesco Paolo

2017-08-28

Oxycodone is a narcotic drug widely used to alleviate moderate and severe acute and chronic pain. Variability in analgesic efficacy could be explained by inter-subject variations in plasma concentrations of parent drug and its active metabolite, oxymorphone. To evaluate patient compliance and to set up therapeutic drug monitoring (TDM), an ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) assay was developed and validated for the parent drug and its major metabolites noroxycodone and oxymorphone. Extraction of analytes from plasma and urine samples was obtained by simple liquid-liquid extraction. The chromatographic separation was achieved with a reversed phase column using a linear gradient elution with two solvents: acetic acid 1% in water and methanol. The separated analytes were detected with a triple quadrupole mass spectrometer operated in multiple reaction monitoring (MRM) mode via positive electrospray ionization (ESI). Separation of analytes was obtained in less than 5 min. Linear calibration curves for all the analytes under investigation in urine and plasma samples showed determination coefficients (r2) equal or higher than 0.990. Mean absolute analytical recoveries were always above 86%. Intra- and inter-assay precision (measured as coefficient of variation, CV%) and accuracy (measured as % error) values were always better than 13%. Limit of detection at 0.06 and 0.15 ng/mL and limit of quantification at 0.2 and 0.5 ng/mL for plasma and urine samples, respectively, were adequate for the purpose of the present study. Rapid extraction, identification and quantification of oxycodone and its metabolites both in urine and plasma by UHPLC-MS/MS assay was tested for its feasibility in clinical samples and provided excellent results for rapid and effective drug testing in patients under oxycodone treatment.

Coumestrol and its metabolite in mares' plasma after ingestion of phytoestrogen-rich plants: potent endocrine disruptors inducing infertility.

Science.gov (United States)

Ferreira-Dias, G; Botelho, M; Zagrajczuk, A; Rebordão, M R; Galvão, A M; Bravo, P Pinto; Piotrowska-Tomala, K; Szóstek, A Z; Wiczkowski, W; Piskula, M; Fradinho, M J; Skarzynski, D J

2013-10-01

Phytoestrogens exist in plants that are present in forages fed to horses. They may compete with 17-β estradiol and influence the estrous cycle. Therefore, the objective was to determine whether coumestrol from clover-mixed pastures is present in mare's plasma after their ingestion (experiment I), and when this phytoestrogen was present in mare's plasma after ingestion (experiment II). The effect of a long-term ingestion of phytoestrogens on estrous cycle disruption was assessed (experiment III; clinical case). Experiment I was carried out in nonpregnant anestrous and cyclic Lusitano mares (n = 14) kept on clover and grass-mixed pastures, and supplemented with concentrate and hay or cereal straw. Blood and feedstuff were obtained from November to March. In experiment II, stabled cyclic Lusitano mares (n = 6) were fed for 14 days with increasing amounts of alfalfa pellets (250 g to 1 kg/day). Sequential blood samples were obtained for 8 hours after feed intake on Day 0 (control) and on Days 13 and 14 (1 kg/day alfalfa pellets). Experiment III mares were fed with a mixture of alfalfa and clover haylage for 5 months (group 1; n = 4) or for 9 months (group 2; n = 12). Estrous cycle was determined on the basis of plasma estradiol (E2), progesterone (P4), and ultrasound (experiment III). Concentrations of phytoestrogen coumestrol and its metabolite methoxycoumestrol were determined by high-performance liquid chromatography coupled with mass spectrometry. Phytoestrogens decreased in pasture from November until March (P haylage) than in group 1, after haylage withdrawal (P < 0.001). These data show that in the mare, coumestrol and its metabolite increase in blood after ingestion of estrogenic plants and can influence reproduction in mares as potent endocrine disruptors. Copyright © 2013 Elsevier Inc. All rights reserved.

A single LC-tandem mass spectrometry method for the simultaneous determination of 14 antimalarial drugs and their metabolites in human plasma.

Science.gov (United States)

Hodel, E M; Zanolari, B; Mercier, T; Biollaz, J; Keiser, J; Olliaro, P; Genton, B; Decosterd, L A

2009-04-01

Among the various determinants of treatment response, the achievement of sufficient blood levels is essential for curing malaria. For helping us at improving our current understanding of antimalarial drugs pharmacokinetics, efficacy and toxicity, we have developed a liquid chromatography-tandem mass spectrometry method (LC-MS/MS) requiring 200mul of plasma for the simultaneous determination of 14 antimalarial drugs and their metabolites which are the components of the current first-line combination treatments for malaria (artemether, artesunate, dihydroartemisinin, amodiaquine, N-desethyl-amodiaquine, lumefantrine, desbutyl-lumefantrine, piperaquine, pyronaridine, mefloquine, chloroquine, quinine, pyrimethamine and sulfadoxine). Plasma is purified by a combination of protein precipitation, evaporation and reconstitution in methanol/ammonium formate 20mM (pH 4.0) 1:1. Reverse-phase chromatographic separation of antimalarial drugs is obtained using a gradient elution of 20mM ammonium formate and acetonitrile both containing 0.5% formic acid, followed by rinsing and re-equilibration to the initial solvent composition up to 21min. Analyte quantification, using matrix-matched calibration samples, is performed by electro-spray ionization-triple quadrupole mass spectrometry by selected reaction monitoring detection in the positive mode. The method was validated according to FDA recommendations, including assessment of extraction yield, matrix effect variability, overall process efficiency, standard addition experiments as well as antimalarials short- and long-term stability in plasma. The reactivity of endoperoxide-containing antimalarials in the presence of hemolysis was tested both in vitro and on malaria patients samples. With this method, signal intensity of artemisinin decreased by about 20% in the presence of 0.2% hemolysed red-blood cells in plasma, whereas its derivatives were essentially not affected. The method is precise (inter-day CV%: 3.1-12.6%) and sensitive

Niacin treatment increases plasma homocyst(e)ine levels.

Science.gov (United States)

Garg, R; Malinow, M; Pettinger, M; Upson, B; Hunninghake, D

1999-12-01

Studies have reported high levels of plasma homocyst(e)ine as an independent risk factor for arterial occlusive disease. The Cholesterol Lowering Atherosclerosis Study reported an increase in plasma homocyst(e)ine levels in patients receiving both colestipol and niacin compared with placebo. Thus the objective of this study was to examine the effect of niacin treatment on plasma homocyst(e)ine levels. The Arterial Disease Multiple Intervention Trial, a multicenter randomized, placebo-controlled trial, examined the effect of niacin compared with placebo on homocyst(e)ine in a subset of 52 participants with peripheral arterial disease. During the screening phase, titration of niacin dose from 100 mg to 1000 mg daily resulted in a 17% increase in mean plasma homocyst(e)ine level from 13.1 +/- 4.4 micromol/L to 15.3 +/- 5.6 micromol/L (P ine levels in the niacin group and a 7% decrease in the placebo group (P =.0001). This difference remained statistically significant at the end of follow-up at 48 weeks. Niacin substantially increased plasma homocyst(e)ine levels, which could potentially reduce the expected benefits of niacin associated with lipoprotein modification. However, plasma homocyst(e)ine levels can be decreased by folic acid supplementation. Thus further studies are needed to determine whether B vitamin supplementation to patients undergoing long-term niacin treatment would be beneficial.

Characterization of the radiolabeled metabolite of tau PET tracer 18F-THK5351

International Nuclear Information System (INIS)

Harada, Ryuichi; Furumoto, Shozo; Tago, Tetsuro; Iwata, Ren; Tashiro, Manabu; Katsutoshi, Furukawa; Ishiki, Aiko; Tomita, Naoki; Arai, Hiroyuki; Yanai, Kazuhiko; Kudo, Yukitsuka; Okamura, Nobuyuki

2016-01-01

18 F-THK5351 is a novel radiotracer developed for in vivo imaging of tau pathology in the brain. For the quantitative assessment of tau deposits in the brain, it is important that the radioactive metabolite does not enter the brain and that it does not bind to tau fibrils. The purpose of the study was to identify a radiolabeled metabolite of 18 F-THK5351 in blood samples from human subjects and to characterize its pharmacological properties. Venous blood samples were collected from three human subjects after injection of 18 F-THK5351 and the plasma metabolite was measured by high performance thin layer chromatography. In addition, mass spectrometry analysis and enzymatic assays were used to identify this metabolite. Mice were used to investigate the blood-brain barrier permeability of the radioactive metabolite. Furthermore, the binding ability of the metabolite to tau aggregates was evaluated using autoradiography and binding assays using human brain samples. About 13 % of the unmetabolized radiotracer was detectable in human plasma at 60 min following the injection of 18 F-THK5351. The isolated radiometabolite of 18 F-THK5351 was the sulphoconjugate of THK5351. This metabolite could be produced in vitro by incubating THK5351 with liver but not brain homogenates. The metabolite did not penetrate the blood-brain barrier in mice, and exhibited little binding to tau protein aggregates in post-mortem human brain samples. These results suggest that the sole metabolite detectable in plasma seems to be generated outside the brain and does not cross into the brain, which does not affect quantitative analysis of PET images. (orig.)

Antipyrine metabolite formation and excretion in patients with chronic renal failure

NARCIS (Netherlands)

Teunissen, M W; Kampf, D; Roots, I; Vermeulen, N P; Breimer, D D

1985-01-01

In the present study the influence of chronic renal insufficiency on antipyrine clearance, metabolite formation and excretion was investigated in 8 patients. After oral administration of antipyrine, the parent compound, its metabolites and their conjugates were assayed in plasma and urine. Besides

Altered levels of acetylcholinesterase in Alzheimer plasma.

Directory of Open Access Journals (Sweden)

María-Salud García-Ayllón

Full Text Available BACKGROUND: Many studies have been conducted in an extensive effort to identify alterations in blood cholinesterase levels as a consequence of disease, including the analysis of acetylcholinesterase (AChE in plasma. Conventional assays using selective cholinesterase inhibitors have not been particularly successful as excess amounts of butyrylcholinesterase (BuChE pose a major problem. PRINCIPAL FINDINGS: Here we have estimated the levels of AChE activity in human plasma by first immunoprecipitating BuChE and measuring AChE activity in the immunodepleted plasma. Human plasma AChE activity levels were approximately 20 nmol/min/mL, about 160 times lower than BuChE. The majority of AChE species are the light G(1+G(2 forms and not G(4 tetramers. The levels and pattern of the molecular forms are similar to that observed in individuals with silent BuChE. We have also compared plasma AChE with the enzyme pattern obtained from human liver, red blood cells, cerebrospinal fluid (CSF and brain, by sedimentation analysis, Western blotting and lectin-binding analysis. Finally, a selective increase of AChE activity was detected in plasma from Alzheimer's disease (AD patients compared to age and gender-matched controls. This increase correlates with an increase in the G(1+G(2 forms, the subset of AChE species which are increased in Alzheimer's brain. Western blot analysis demonstrated that a 78 kDa immunoreactive AChE protein band was also increased in Alzheimer's plasma, attributed in part to AChE-T subunits common in brain and CSF. CONCLUSION: Plasma AChE might have potential as an indicator of disease progress and prognosis in AD and warrants further investigation.

Multi-Accuracy-Level Burning Plasma Simulations

International Nuclear Information System (INIS)

Artaud, J. F.; Basiuk, V.; Garcia, J.; Giruzzi, G.; Huynh, P.; Huysmans, G.; Imbeaux, F.; Johner, J.; Scheider, M.

2007-01-01

The design of a reactor grade tokamak is based on a hierarchy of tools. We present here three codes that are presently used for the simulations of burning plasmas. At the first level there is a 0-dimensional code that allows to choose a reasonable range of global parameters; in our case the HELIOS code was used for this task. For the second level we have developed a mixed 0-D / 1-D code called METIS that allows to study the main properties of a burning plasma, including profiles and all heat and current sources, but always under the constraint of energy and other empirical scaling laws. METIS is a fast code that permits to perform a large number of runs (a run takes about one minute) and design the main features of a scenario, or validate the results of the 0-D code on a full time evolution. At the top level, we used the full 1D1/2 suite of codes CRONOS that gives access to a detailed study of the plasma profiles evolution. CRONOS can use a variety of modules for source terms and transport coefficients computation with different level of complexity and accuracy: from simple estimators to highly sophisticated physics calculations. Thus it is possible to vary the accuracy of burning plasma simulations, as a trade-off with computation time. A wide range of scenario studies can thus be made with CRONOS and then validated with post-processing tools like MHD stability analysis. We will present in this paper results of this multi-level analysis applied to the ITER hybrid scenario. This specific example will illustrate the importance of having several tools for the study of burning plasma scenarios, especially in a domain that present devices cannot access experimentally. (Author)

Plasma membrane ATPases

DEFF Research Database (Denmark)

Palmgren, Michael Broberg; Bækgaard, Lone; Lopez Marques, Rosa Laura

2011-01-01

The plasma membrane separates the cellular contents from the surrounding environment. Nutrients must enter through the plasma membrane in order to reach the cell interior, and toxic metabolites and several ions leave the cell by traveling across the same barrier. Biological pumps in the plasma me...

Determination of metabolite of nicergoline in human plasma by high-performance liquid chromatography and its application in pharmacokinetic studies

Directory of Open Access Journals (Sweden)

Rong Zheng

2012-02-01

Full Text Available A fast, simple and sensitive high performance liquid chromatographic (HPLC method has been developed for determination of 10α-methoxy-6-methyl ergoline-8β-methanol (MDL, a main metabolite of nicergoline in human plasma. One-step liquid–liquid extraction (LLE with diethyl ether was employed as the sample preparation method. Tizanidine hydrochloride was selected as the internal standard (IS. Analysis was carried out on a Diamonsil ODS column (150 mm×4.6 mm, 5 μm using acetonitrile–ammonium acetate (0.1 mol/L (15/85, v/v as mobile phase at detection wavelength of 224 nm. The calibration curves were linear over the range of 2.288–73.2 ng/mL with a lower limit of quantitation (LLOQ of 2.288 ng/mL. The intra- and inter-day precision values were below 13% and the recoveries were from 74.47% to 83.20% at three quality control levels. The method herein described was successfully applied in a randomized crossover bioequivalence study of two different nicergoline preparations after administration of 30 mg in 20 healthy volunteers. Keywords: Nicergoline, 10α-methoxy-6-methylergoline-8β-methanol (MDL, HPLC, Plasma-drug concentration, Bioequivalence study

Longitudinal plasma metabolic profiles, infant feeding, and islet autoimmunity in the MIDIA study

DEFF Research Database (Denmark)

Jørgenrud, Benedicte; Stene, Lars C; Tapia, German

2017-01-01

Aims: The aim of this study was to investigate the longitudinal plasma metabolic profiles in healthy infants and the potential association with breastfeeding duration and islet autoantibodies predictive of type 1 diabetes. Method: Up to four longitudinal plasma samples from age 3 months from case......, and lower levels of methionine and 3,4-dihydroxybutyric acid at 3 months of age. Conclusions: Plasma levels of several small, polar metabolites changed with age during early childhood, independent of later islet autoimmunity status and sex. Breastfeeding was associated with higher levels of branched......-chain amino acids, and lower levels of methionine and 3,4-dihydroxybutyric acid....

Unbiased Scanning Method and Data Banking Approach Using Ultra-High Performance Liquid Chromatography Coupled with High-Resolution Mass Spectrometry for Quantitative Comparison of Metabolite Exposure in Plasma across Species Analyzed at Different Dates.

Science.gov (United States)

Gao, Hongying; Deng, Shibing; Obach, R Scott

2015-12-01

An unbiased scanning methodology using ultra high-performance liquid chromatography coupled with high-resolution mass spectrometry was used to bank data and plasma samples for comparing the data generated at different dates. This method was applied to bank the data generated earlier in animal samples and then to compare the exposure to metabolites in animal versus human for safety assessment. With neither authentic standards nor prior knowledge of the identities and structures of metabolites, full scans for precursor ions and all ion fragments (AIF) were employed with a generic gradient LC method to analyze plasma samples at positive and negative polarity, respectively. In a total of 22 tested drugs and metabolites, 21 analytes were detected using this unbiased scanning method except that naproxen was not detected due to low sensitivity at negative polarity and interference at positive polarity; and 4'- or 5-hydroxy diclofenac was not separated by a generic UPLC method. Statistical analysis of the peak area ratios of the analytes versus the internal standard in five repetitive analyses over approximately 1 year demonstrated that the analysis variation was significantly different from sample instability. The confidence limits for comparing the exposure using peak area ratio of metabolites in animal plasma versus human plasma measured over approximately 1 year apart were comparable to the analysis undertaken side by side on the same days. These statistical analysis results showed it was feasible to compare data generated at different dates with neither authentic standards nor prior knowledge of the analytes.

Inhibiting mitochondrial β-oxidation selectively reduces levels of nonenzymatic oxidative polyunsaturated fatty acid metabolites in the brain.

Science.gov (United States)

Chen, Chuck T; Trépanier, Marc-Olivier; Hopperton, Kathryn E; Domenichiello, Anthony F; Masoodi, Mojgan; Bazinet, Richard P

2014-03-01

Schönfeld and Reiser recently hypothesized that fatty acid β-oxidation is a source of oxidative stress in the brain. To test this hypothesis, we inhibited brain mitochondrial β-oxidation with methyl palmoxirate (MEP) and measured oxidative polyunsaturated fatty acid (PUFA) metabolites in the rat brain. Upon MEP treatment, levels of several nonenzymatic auto-oxidative PUFA metabolites were reduced with few effects on enzymatically derived metabolites. Our finding confirms the hypothesis that reduced fatty acid β-oxidation decreases oxidative stress in the brain and β-oxidation inhibitors may be a novel therapeutic approach for brain disorders associated with oxidative stress.

Characterization of the radiolabeled metabolite of tau PET tracer {sup 18}F-THK5351

Energy Technology Data Exchange (ETDEWEB)

Harada, Ryuichi [Tohoku University, Division of Neuro-imaging, Institute of Development, Aging and Cancer, Sendai (Japan); Furumoto, Shozo; Tago, Tetsuro; Iwata, Ren; Tashiro, Manabu [Tohoku University, Cyclotron and Radioisotope Center, Sendai (Japan); Katsutoshi, Furukawa; Ishiki, Aiko; Tomita, Naoki; Arai, Hiroyuki [Tohoku University, Department of Geriatrics and Gerontology, Institute of Development, Aging and Cancer, Sendai (Japan); Yanai, Kazuhiko [Tohoku University, Cyclotron and Radioisotope Center, Sendai (Japan); Tohoku University School of Medicine, Department of Pharmacology, Sendai (Japan); Kudo, Yukitsuka [Tohoku University, Division of Neuro-imaging, Institute of Development, Aging and Cancer, Sendai (Japan); Tohoku University, Cyclotron and Radioisotope Center, Sendai (Japan); Okamura, Nobuyuki [Tohoku University, Division of Neuro-imaging, Institute of Development, Aging and Cancer, Sendai (Japan); Tohoku University, Cyclotron and Radioisotope Center, Sendai (Japan); Tohoku Medical and Pharmaceutical University, Division of Pharmacology, Faculty of Medicine, Sendai (Japan)

2016-11-15

{sup 18}F-THK5351 is a novel radiotracer developed for in vivo imaging of tau pathology in the brain. For the quantitative assessment of tau deposits in the brain, it is important that the radioactive metabolite does not enter the brain and that it does not bind to tau fibrils. The purpose of the study was to identify a radiolabeled metabolite of {sup 18}F-THK5351 in blood samples from human subjects and to characterize its pharmacological properties. Venous blood samples were collected from three human subjects after injection of {sup 18}F-THK5351 and the plasma metabolite was measured by high performance thin layer chromatography. In addition, mass spectrometry analysis and enzymatic assays were used to identify this metabolite. Mice were used to investigate the blood-brain barrier permeability of the radioactive metabolite. Furthermore, the binding ability of the metabolite to tau aggregates was evaluated using autoradiography and binding assays using human brain samples. About 13 % of the unmetabolized radiotracer was detectable in human plasma at 60 min following the injection of {sup 18}F-THK5351. The isolated radiometabolite of {sup 18}F-THK5351 was the sulphoconjugate of THK5351. This metabolite could be produced in vitro by incubating THK5351 with liver but not brain homogenates. The metabolite did not penetrate the blood-brain barrier in mice, and exhibited little binding to tau protein aggregates in post-mortem human brain samples. These results suggest that the sole metabolite detectable in plasma seems to be generated outside the brain and does not cross into the brain, which does not affect quantitative analysis of PET images. (orig.)

Increased plasma agmatine levels in patients with schizophrenia.

Science.gov (United States)

Uzbay, Tayfun; Goktalay, Gokhan; Kayir, Hakan; Eker, Salih S; Sarandol, Asli; Oral, Sema; Buyukuysal, Levent; Ulusoy, Gokhan; Kirli, Selcuk

2013-08-01

Agmatine is an endogenous substance, synthesized from l-arginine, and it is proposed to be a new neurotransmitter. Preclinical studies indicated that agmatine may have an important role in the pathophysiology of schizophrenia. This study was organized to investigate plasma agmatine in patients with schizophrenia and in healthy controls. Eighteen patients with schizophrenia and 19 healthy individuals constituted the subjects. Agmatine levels in the plasma were measured using the HPLC method. The S100B protein level, which is a peripheral biomarker for brain damage, was also measured using the ELISA method. While plasma levels of agmatine in patients with schizophrenia were significantly increased (p agmatine levels as a clinical diagnostic test would significantly differentiate between patients with schizophrenia and those in the control group (predictive value: 0.969; p  0.05). A multiple regression analysis revealed that the age of the patient and the severity of the illness, as indicated by the PANSS score, significantly contributed the plasma agmatine levels in patients with schizophrenia. These results support the hypothesis that an excess agmatine release is important in the development of schizophrenia. The findings also imply that the plasma agmatine level may be a potential biomarker of schizophrenia. Copyright © 2013 Elsevier Ltd. All rights reserved.

Plasma levels of d1-3-(1,1-dimethylheptyl)-6,6aβ,7,8,10,10aα-hexahydro-1-hydroxy-6,6-dimethyl-9H-dibenzo[b,d]pyran-9-one (Lilly 109514) by quantitative mass fragmentography

International Nuclear Information System (INIS)

Sullivan, H.R.; Kau, D.L.K.; Wood, P.G.

1975-01-01

Lilly compound 109514 produces alterations in behavioral parameters in laboratory animals. Its relaxant and sedative properties are being studied clinically. A quantitative mass fragmentography (QMF) method for Lilly 109514 has been developed which is sensitive to 2 pmoles/4 ml sample. A similar assay has been developed for the major metabolite (formed by reduction of the 9-keto group). Both assays use deuterium labeled internal standards. Plasma concentrations of the parent drug and the metabolite were determined in dogs following oral administration of single and multiple 400 μg/kg doses of Lilly 109514. Results indicated the drug to be rapidly absorbed and metabolized in this species. Concentrations of the metabolite were significantly higher than those of the parent drug. These results implied that multiple-dosing of Lilly 109514 did not cause induction of metabolizing enzymes or other alterations of the metabolic process in the dog. Determination of the plasma concentrations of the parent drug and metabolite following i.v. administration have permitted the calculation of bioavailability and absorption data. The ability to follow plasma levels for 48 hours after a single i.v. administration of 100 μg/kg of 109514 graphically illustrates the value of quantitative mass fragmentography in kinetic studies of cannabinoids

PHARMACOKINETICS OF TRAMADOL HYDROCHLORIDE AND ITS METABOLITE O-DESMETHYLTRAMADOL FOLLOWING A SINGLE, ORALLY ADMINISTERED DOSE IN CALIFORNIA SEA LIONS (ZALOPHUS CALIFORNIANUS).

Science.gov (United States)

Boonstra, Jennifer L; Barbosa, Lorraine; Van Bonn, William G; Johnson, Shawn P; Gulland, Frances M D; Cox, Sherry K; Martin-Jimenez, Tomas

2015-09-01

Tramadol is a synthetic, centrally acting, opiate-like analgesic that is structurally related to codeine and morphine. The objective of this study was to determine the pharmacokinetics of tramadol hydrochloride and its major active metabolite O-desmethyltramadol (M1) in the California sea lion (Zalophus californianus). A single dose of tramadol was administered orally in fish at 2 mg/kg to a total of 15 wild California sea lions admitted for rehabilitation. Twenty-four total blood samples were collected post drug administration at 10, 20, 30, and 45 min and at 1, 3, 5, 6, 8, 12, and 24 hr. Blood plasma was separated and stored at -80°C until analysis with high-performance liquid chromatography was performed to determine levels of tramadol and M1, the major active metabolite. The results indicate that the plasma levels of parent tramadol are low or negligible during the first 30-45 min and then reach the predicted mean maximum plasma concentration of 358 ng/ml at 1.52 hr. The M1 metabolite was not detectable in 21 of 24 plasma samples, below the level of quantification of 5 ng/ml in one sample, and detectable at 11 and 17 ng/ml in two of the samples. This study suggests that a 2 mg/kg dose would need to be administered every 6-8 hr to maintain concentrations of tramadol above the minimum human analgesic level for mild to moderate pain. Based on dosing simulations, a dose of 4 mg/kg q8 hr or q12 hr, on average, may represent an adequate compromise, but further studies are needed using a larger sample size. Pharmacodynamic studies are warranted to determine if tramadol provides analgesic effects in this species. The potential for tramadol toxicosis at any dose also has not been determined in this species.

Metabolomic study of plasma from female mink (Neovison vison) with low and high residual feed intake during restrictive and ad libitum feeding

DEFF Research Database (Denmark)

Hedemann, Mette Skou; Damgaard, Birthe Marie

2012-01-01

was high during restrictive feeding, e.g. betaine, carnitine, and creatine. During ad libitum feeding the plasma level of metabolites that can be characterized as biomarkers of meat intake (creatinine, carnosine, 1- and 3 methylhistidine) was high. The plasma level of lysophosphatidylcholine species......Metabolite profiling may elucidate changes in metabolic pathways under various physiological or nutritional conditions. In the present study two groups of female mink characterized as having a high (16 mink) or low (14 mink) residual feed intake were investigated during restrictive and ad libitum...

Effects of prenatal exposure to hydoxylated PCB metabolites and some brominated flame retardants on the development of rats

Energy Technology Data Exchange (ETDEWEB)

Buitenhuis, C.; Cenijn, P.C.; Velzen, M. van; Gutleb, A.C.; Legler, J. [Institute for Environmental Studies (IVM), Amsterdam (Netherlands); Lilienthal, H. [Heinrich Univ., Duesseldorf (Germany). Dept. Neurobehavioural Toxicology, Medical Institute of Environmental Hygiene; Malmberg, T.; Bergman, Aa. [Stockholm Univ. (Sweden). Dept. of Environmental Chemistry; Brouwer, A.

2004-09-15

Possible human health effects from low-level exposure to environmental chemicals are an issue that has attracted much attention. Environmental compounds that may play a role are those that may disrupt endocrine function. Organohalogen compounds, and in particular their hydroxylated metabolites, show a striking resemblance to steroid hormones.The main objective of this research is to investigate comparative pathways of early life-stage exposure and long-term effects for several classes of organohalogens, including polychlorinated biphenyls (PCBs) and flame retardants, polybrominated bisphenols and -diphenylethers, and their hydroxylated metabolites. Due to their prevalence in human plasma, the hydroxylated PCB metabolites 4-OH-CB107 and 4-OH-CB187, as well as 6-OH-BDE47 and 2,4,6- tribromophenol, were selected as test compounds. BDE 47 has been included as a test compound due to its relatively high levels in the environment and biota, whereas tetrabromobisphenol A (TBBPA) was selected because of its high volume production. The in vivo studies involved prenatal exposure of rats to test compounds during critical stages of gonadal development and were focussed on low dose effects. Several endpoints were investigated, including endocrine (thyroid and sex steroid hormones) effects, developmental landmarks, sexual and neurobehavioural development. Blood plasma and tissue levels of test compounds were analysed to determine transplacental transfer of (hydroxylated) organohalogens.

Rikkunshito Ameliorates Cancer Cachexia Partly through Elevation of Glucarate in Plasma

Directory of Open Access Journals (Sweden)

Katsuya Ohbuchi

2015-01-01

Full Text Available Cancer cachexia, which is characterized by decreased food intake, weight loss and systemic inflammation, increases patient’s morbidity and mortality. We previously showed that rikkunshito (RKT, a Japanese traditional herbal medicine (Kampo, ameliorated the symptoms of cancer cachexia through ghrelin signaling-dependent and independent pathways. To investigate other mechanisms of RKT action in cancer cachexia, we performed metabolome analysis of plasma in a rat model bearing the Yoshida AH-130 hepatoma. A total of 110 metabolites were detected in plasma and RKT treatment significantly altered levels of 23 of those metabolites in cachexia model rats. Among them, glucarate, which is known to have anticarcinogenic activity through detoxification of carcinogens via inhibition of β-glucuronidase, was increased in plasma following administration of RKT. In our AH-130 ascites-induced cachexia rat model, administration of glucarate delayed onset of weight loss, improved muscle atrophy, and reduced ascites content. Additionally, glucarate reduced levels of plasma interferon-γ (IFN-γ in tumor-bearing rats and was also found to suppress LPS-induced IFN-γ expression in splenocytes in vitro. These results suggest that glucarate has anti-inflammatory activity via a direct effect on immune host cells and suggest that RKT may also ameliorate inflammation partly through the elevation of glucarate in plasma.

Plasma kisspeptin levels in male cases with hypogonadism.

Science.gov (United States)

Kotani, Masato; Katagiri, Fumihiko; Hirai, Tsuyoshi; Kagawa, Jiro

2014-01-01

The hypothalamic hormone kisspeptin (metastin) regulates human reproduction by modulating gonadotropin-releasing hormone (GnRH) secretion. Kisspeptin is detected in peripheral blood, although GnRH is not. In this study, we measured plasma kisspeptin levels in four male cases with hypogonadism and seven normal male controls using enzyme immunoassay (EIA) to elucidate the clinical implications of kisspeptin levels in male hypogonadism. The results showed a variety of plasma kisspeptin levels: 6.0 fmol/mL in a male with isolated hypogonadotropic hypogonadism (IHH), 43.2 fmol/mL in a male with Kallmann's syndrome, 40.7 fmol/mL in a male with azoospermia, 323.2 fmol/mL in a male with hypergonadotropic hypogonadism, and 12.3 ± 2.5 fmol/mL (mean ± SD) in seven normal controls. Except for the case with IHH, the plasma kisspetin levels were elevated in the three cases with Kallmann's syndrome, azoospermia, and hypergonadotropic hypogonadism. The reason why the three cases had high values was their lesions were downstream of the kisspeptin neuron in the hypothalamic-pituitary-gonadal axis, suggesting that elevated kisspeptin levels were implicated in hypothalamic kisspeptin secretion under decreased negative feedback of gonadal steroids. The result that the plasma kisspeptin levels were decreased by gonadotropin therapy in the case with Kallmann's syndrome supported this hypothesis. In conclusion, to measure plasma kisspeptin levels could be useful for better understanding of male hypogonadism.

Effect of the long-term regular intake of virgin olive oil on the phenolic metabolites in human fasting plasma.

Science.gov (United States)

Valls, Rosa-Maria; Soler, Aranzazu; Girona, Josefa; Heras, Mercedes; Romero, Maria-Paz; Covas, Maria-Isabel; Solà, Rosa; Masana, Lluis; Motilva, Maria-Jose

2010-09-21

The effect of repeated consumption of virgin olive oil on endogenous phenolic metabolites of fasting plasma is unknown. For this reason, we hypothesized that regular long-term virgin olive oil intake could have an indirect protection effect on the endogenous phenols. Thus, the aim of the study was to determine the phenolic profile of human plasma in a fasting state of long-term regular virgin olive oil consumers, using the fasting plasma of non-consumers as a natural control. Forty participants living in the area of Reus (Catalonia, Spain) were selected, 20 life-long regular consumers of virgin olive oil and a natural control of 20 non-consumers, the latter being Rumanians who dislike the taste of olive oil. The diet was obtained from 3-day food records. The results showed similar phenolic composition of fasting plasmas of the two volunteer groups. Of special interest is that more of the compounds quantified showed higher concentration in fasting plasma from habitual virgin olive oil consumers. The compounds were semi-quantified using caffeic acid as the calibration standard. The quantification of fasting consumer's plasma showed higher concentration of a hydroxyflavanone type compound (2.90+/-0.04 microM vs 1.5+/-0.04 microM) and a catecholamine derivative (0.70+/-0.03 microM vs 0.56+/-0.03 microM) than the plasma of non-consumers (P<0.05). The results suggest an indirect protective mechanism of long-term regular virgin olive oil consumption related to the protection of the endogenous antioxidant system. Copyright 2010 Elsevier B.V. All rights reserved.

Optimization and validation of bioanalytical SPE – HPLC method for the simultaneous determination of carbamazepine and its main metabolite, carbamazepine-10, 11-epoxide, in plasma

Directory of Open Access Journals (Sweden)

Jasmina Tonic – Ribarska

2012-03-01

Full Text Available Carbamazepine is widely used as an antiepileptic drug in the treatment of partial and generalized tonic-clonic seizures. Carbamazepine 10,11-epoxide is the most important metabolite of carbamazepine, because it is a pharmacologically active compound with anticonvulsant properties. According to that, the routine analysis of carbamazepine 10,11-epoxide along with carbamazepine may provide optimal therapeutic monitoring of carbamazepine treatment. The aim of this study was to optimize and validate a simple and reliable solid - phase extraction method followed by RP-HPLC for the simultaneous determination of plasma levels of carbamazepine and carbamazepine-10,11-epoxide, in order to assure the implementation of the method for therapeutic monitoring. The extraction of the analytes from the plasma samples was performed by means of a solid-phase extraction procedure. The separation was carried out on a reversed-phase column using isocratic elution with acetonitrile and water (35:65, v/v as a mobile phase. The temperature was 30°C and UV detection was set at 220 nm. The extraction yield values were more than 98% for all analytes, measured at four concentration levels of the linear concentration range. The method displayed excellent selectivity, sensitivity, linearity, precision and accuracy. Stability studies indicate that stock solutions and plasma samples were stabile under different storage conditions at least during the observed period. The method was successfully applied to determine the carbamazepine and carbamazepine-10,11-epoxide in plasma of epileptic patients treated with carbamazepine as monotherapy and in polytherapy. In conclusion, the proposed method is suitable for application in therapeutic drug monitoring of epileptic patients undergoing treatment with carbamazepine.

Removal of uremic retention products by hemodialysis is coupled with indiscriminate loss of vital metabolites.

Science.gov (United States)

Zhang, Zhi-Hao; Mao, Jia-Rong; Chen, Hua; Su, Wei; Zhang, Yuan; Zhang, Li; Chen, Dan-Qian; Zhao, Ying-Yong; Vaziri, Nosratola D

2017-12-01

Although dialysis ameliorates uremia and fluid and electrolytes disorders, annual mortality rate remains high in dialysis population reflecting its shortcoming in replacing renal function. Unlike the normal kidney, dialysis causes dramatic shifts in volume and composition of body fluids and indiscriminate removal of vital solutes. Present study was undertaken to determine the impact of hemodialysis on plasma metabolites in end-stage renal disease (ESRD) patients. 80 hemodialysis patients and 80 age/gender-matched healthy controls were enrolled in the study. Using ultra performance liquid chromatography-high-definition mass spectrometry, we measured plasma metabolites before, during, and after hemodialysis procedure and in blood entering and leaving the dialysis filter. Principal component analysis revealed significant difference in concentration of 214 metabolites between healthy control and ESRD patients' pre-dialysis plasma (126 increased and 88 reduced in ESRD group). Comparison of post-dialysis with pre-dialysis data revealed significant changes in the 362 metabolites. Among ESI + metabolites 195 decreased and 55 increased and among ESI - metabolites 82 decreased and 30 increased following hemodialysis. Single blood passage through the dialyzer caused significant changes in 323 metabolites. Comparison of ESRD patients' post-hemodialysis with healthy subjects' data revealed marked differences in metabolic profiles. We identified 55 of the 362 differential metabolites including well known uremic toxins, waste products and vital biological compounds. In addition to uremic toxins and waste products hemodialysis removes large number of identified and as-yet un-identified metabolites. Depletion of vital biological compounds by dialysis may contribute to the high morbidity and annual mortality rate in this population. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

Ultra-sensitive LC-MS/MS method for the quantification of gemcitabine and its metabolite 2',2'-difluorodeoxyuridine in human plasma for a microdose clinical trial.

Science.gov (United States)

van Nuland, M; Hillebrand, M J X; Rosing, H; Burgers, J A; Schellens, J H M; Beijnen, J H

2018-03-20

In microdose clinical trials a maximum of 100 μg of drug substance is administered to participants, in order to determine the pharmacokinetic properties of the agents. Measuring low plasma concentrations after administration of a microdose is challenging and requires the use of ulta-sensitive equipment. Novel liquid chromatography-mass spectrometry (LC-MS/MS) platforms can be used for quantification of low drug plasma levels. Here we describe the development and validation of an LC-MS/MS method for quantification of gemcitabine and its metabolite 2',2'-difluorodeoxyuridine (dFdU) in the low picogram per milliliter range to support a microdose trial. The validated assay ranges from 2.5-500 pg/mL for gemcitabine and 250-50,000 pg/mL for dFdU were linear, with a correlation coefficient (r 2 ) of 0.996 or better. Sample preparation with solid phase extraction provided a good and reproducible recovery. All results were within the acceptance criteria of the latest US FDA guidance and EMA guidelines. In addition, the method was successfully applied to measure plasma concentrations of gemcitabine in a patient after administration of a microdose of gemcitabine. Copyright © 2017 Elsevier B.V. All rights reserved.

Determination of flutamide and two major metabolites using HPLC-DAD and HPTLC methods.

Science.gov (United States)

Abdelwahab, Nada S; Elshemy, Heba A H; Farid, Nehal F

2018-01-25

Flutamide is a potential antineoplastic drug classified as an anti-androgen. It is a therapy for men with advanced prostate cancer, administered orally after which it undergoes extensively first pass metabolism in the liver with the production of several metabolites. These metabolites are predominantly excreted in urine. One of the important metabolites in plasma is 4-nitro-3-(trifluoromethyl)phenylamine (Flu-1), while the main metabolite in urine is 2-amino-5-nitro-4-(trifluoromethyl)phenol (Flu-3). In this work the two metabolites, Flu-1 and Flu-3, have been synthesized, and then structural confirmation has been carried out by HNMR analysis. Efforts were exerted to develop chromatographic methods for resolving Flutamide and its metabolites with the use of acceptable solvents without affecting the efficiency of the methods. The drug along with its metabolites were quantitatively analyzed in pure form, human urine, and plasma samples using two chromatographic methods, HPTLC and HPLC-DAD methods. FDA guidelines for bio-analytical method validation were followed and USP recommendations were used for analytical method validation. Interference from excipients has been tested by application of the methods to pharmaceutical tablets. No significant difference was found between the proposed methods and the official one when they were statistically compared at p value of 0.05%.

Characterisation of the appearance of radioactive metabolites in monkey and human plasma from the 5-HT1A receptor radioligand, [carbonyl-11C]WAY-100635 - explanation of high signal contrast in PET and an aid to biomathematical modelling

International Nuclear Information System (INIS)

Osman, Safiye; Lundkvist, Camilla; Pike, Victor W.; Halldin, Christer; McCarron, Julie A.; Swahn, Carl-Gunnar; Farde, Lars; Ginovart, Nathalie; Luthra, Sajinder K.; Gunn, Roger N.; Bench, Christopher J.; Sargent, Peter A.; Grasby, Paul M.

1998-01-01

N-(2-(4-(2-Methoxy-phenyl)-1-piperazin-1-yl)ethyl)-N-(2-pyridyl) cyclohexanecarboxamide (WAY-100635), labelled in its amido carbonyl group with 11 C (t 1/2 = 20.4 min), is a promising radioligand for the study of brain 5-HT 1A receptors with positron emission tomography (PET). Thus, in PET experiments in six cynomolgus monkeys and seven healthy male volunteers, [carbonyl- 11 C]WAY-100635 was taken up avidly by brain. Radioactivity was retained in regions rich in 5-HT 1A receptors, such as occipital cortex, temporal cortex and raphe nuclei, but cleared rapidly from cerebellum, a region almost devoid of 5-HT 1A receptors. [Carbonyl- 11 C]WAY-100635 provides about 3- and 10-fold higher signal contrast (receptor-specific to nonspecific binding) than [O-methyl- 11 C]WAY-100635 in receptor-rich areas of monkey and human brain, respectively. To elucidate the effect of label position on radioligand behaviour and to aid in the future biomathematical interpretation of the kinetics of regional cerebral radioactivity uptake in terms of receptor-binding parameters, HPLC was used to measure [carbonyl- 11 C]WAY-100635 and its radioactive metabolites in plasma at various times after intravenous injection. Radioactivity cleared rapidly from monkey and human plasma. Parent radioligand represented 19% of the radioactivity in monkey plasma at 47 min and 8% of the radioactivity in human plasma at 40 min. [Carbonyl- 11 C]desmethyl-WAY-100635 was below detectable limits in monkey plasma and at most a very minor radioactive metabolite in human plasma. [ 11 C]Cyclohexanecarboxylic acid was identified as a significant radioactive metabolite. In human plasma this maximally represented 21% of the radioactivity at 10 min after radioligand injection. All other major radioactive metabolites in monkey and human plasma were even more polar. No-carrier-added [carbonyl- 11 C]cyclohexanecarboxylic acid was prepared in the laboratory and after intravenous administration into cynomolgus monkey was

NEW METABOLITES OF THE DRUG 5-AMINOSALICYLIC ACID .2. N-FORMYL-5-AMINOSALICYLIC ACID

DEFF Research Database (Denmark)

Tjornelund, J.; Hansen, S. H.; Cornett, Claus

1991-01-01

1. A new metabolite of the drug 5-aminosalicylic acid (5-ASA) has been found in urine from pigs and in plasma of humans. The metabolite has been isolated from pig urine using an XAD-2 column and purified using preparative h.p.l.c. 2. The metabolite has been identified as N-formyl-5-ASA (5-formami...

Anti-androgenic activities of diuron and its metabolites in male Nile tilapia (Oreochromis niloticus).

Science.gov (United States)

Pereira, Thiago Scremin Boscolo; Boscolo, Camila Nomura Pereira; Silva, Danilo Grünig Humberto da; Batlouni, Sergio Ricardo; Schlenk, Daniel; Almeida, Eduardo Alves de

2015-07-01

Diuron (3-(3,4-dichlorophenyl)-1,1-dimethylurea) is a widely used herbicide which has been frequently detected in surface waters throughout the world. In vivo bioassay guided fractionation studies indicated that diuron may have estrogenic activity augmented by biotransformation. This study evaluated the effects of diuron and three of its metabolites on plasma hormone concentrations and spermatogenesis of the freshwater fish Nile tilapia (Oreochromis niloticus). Sexually mature male fish were exposed for 25 days to diuron, as well to its metabolites 3,4-dichloroaniline (DCA), 3,4-dichlorophenylurea (DCPU) and 3,4-dichlorophenyl-N-methylurea (DCPMU), at concentrations of 200ng/L. Testosterone levels were decreased by diuron, but had limited effects on gonadal histology. Diuron metabolites, however, caused significant decreases in testosterone and in 11-ketotestosterone, gonadosomatic index, diameter of seminiferous tubules and in the mean percentages of germ cells (spermatids and spermatozoa). We conclude that these metabolites have antiandrogenic activity to male Nile tilapia, potentially causing reproductive impairment in male fish. Copyright © 2015 Elsevier B.V. All rights reserved.

Simultaneous determination of flurbiprofen and its hydroxy metabolite in human plasma by liquid chromatography-tandem mass spectrometry for clinical application.

Science.gov (United States)

Lee, Hye-In; Choi, Chang-Ik; Byeon, Ji-Yeong; Lee, Jung-Eun; Park, So-Young; Kim, Young-Hoon; Kim, Se-Hyung; Lee, Yun-Jeong; Jang, Choon-Gon; Lee, Seok-Yong

2014-11-15

Flurbiprofen (FLB) is one of the phenylalkanoic acid derivatives of non-steroidal anti-inflammatory drugs used for the management of pain and inflammation in patients with arthritis. We developed and validated a rapid and sensitive high-performance liquid chromatography analytical method utilizing tandem mass spectrometry (HPLC-MS/MS) for the simultaneous determination of FLB and its major metabolite, 4'-hydroxyflurbiprofen (4'-OH-FLB), in human plasma. Probenecid was used as an internal standard (IS). After liquid-liquid extraction with methyl t-butyl ether, chromatographic separation of the two analytes was achieved using a reversed-phase Luna C18 column (2.0mm×50mm, 5μm particles) with a mobile phase of 10mM ammonium formate buffer (pH 3.5)-methanol (15:85, v/v) and quantified by MS/MS detection in ESI negative ion mode. The flow rate of the mobile phase was 250μl/min and the retention times of FLB, 4'-OH-FLB, and IS were 1.1, 0.8, and 0.9min, respectively. The calibration curves were linear over a range of 0.01-10μg/ml for FLB and 0.01-1μg/ml for 4'-OH-FLB. The lower limit of quantifications using 100μl of human plasma was 0.01μg/ml for both analytes. The mean accuracy and precision for intra- and inter-run validation of FLB and 4'-OH-FLB were all within acceptable limits. The present HPLC-MS/MS method showed improved sensitivity for quantification of the FLB and its major metabolite in human plasma compared with previously described analytical methods. The validated method was successfully applied to a pharmacokinetic study in humans. Copyright © 2014 Elsevier B.V. All rights reserved.

Insulin induces a shift in lipid and primary carbon metabolites in a model of fasting-induced insulin resistance

Science.gov (United States)

Olmstead, Keedrian I.; La Frano, Michael R.; Fahrmann, Johannes; Grapov, Dmitry; Viscarra, Jose A.; Newman, John W.; Fiehn, Oliver; Crocker, Daniel E.; Filipp, Fabian V.; Ortiz, Rudy M.

2017-01-01

Introduction Prolonged fasting in northern elephant seals (NES) is characterized by a reliance on lipid metabolism, conservation of protein, and reduced plasma insulin. During early fasting, glucose infusion previously reduced plasma free fatty acids (FFA); however, during late-fasting, it induced an atypical elevation in FFA despite comparable increases in insulin during both periods suggestive of a dynamic shift in tissue responsiveness to glucose-stimulated insulin secretion. Objective To better assess the contribution of insulin to this fasting-associated shift in substrate metabolism. Methods We compared the responses of plasma metabolites (amino acids (AA), FFA, endocannabinoids (EC), and primary carbon metabolites (PCM)) to an insulin infusion (65 mU/kg) in early- and late-fasted NES pups (n = 5/group). Plasma samples were collected prior to infusion (T0) and at 10, 30, 60, and 120 min post-infusion, and underwent untargeted and targeted metabolomics analyses utilizing a variety of GC-MS and LC-MS technologies. Results In early fasting, the majority (72%) of metabolite trajectories return to baseline levels within 2 h, but not in late fasting indicative of an increase in tissue sensitivity to insulin. In late-fasting, increases in FFA and ketone pools, coupled with decreases in AA and PCM, indicate a shift toward lipolysis, beta-oxidation, ketone metabolism, and decreased protein catabolism. Conversely, insulin increased PCM AUC in late fasting suggesting that gluconeogenic pathways are activated. Insulin also decreased FFA AUC between early and late fasting suggesting that insulin suppresses triglyceride hydrolysis. Conclusion Naturally adapted tolerance to prolonged fasting in these mammals is likely accomplished by suppressing insulin levels and activity, providing novel insight on the evolution of insulin during a condition of temporary, reversible insulin resistance. PMID:28757815

Plasma levels of acylated ghrelin in patients with functional dyspepsia

Science.gov (United States)

Kim, Yeon Soo; Lee, Joon Seong; Lee, Tae Hee; Cho, Joo Young; Kim, Jin Oh; Kim, Wan Jung; Kim, Hyun Gun; Jeon, Seong Ran; Jeong, Hoe Su

2012-01-01

AIM: To investigate the relationship between plasma acylated ghrelin levels and the pathophysiology of functional dyspepsia. METHODS: Twenty-two female patients with functional dyspepsia and twelve healthy volunteers were recruited for the study. The functional dyspepsia patients were each diagnosed based on the Rome III criteria. Eligible patients completed a questionnaire concerning the severity of 10 symptoms. Plasma acylated ghrelin levels before and after a meal were determined in the study participants using a commercial human acylated enzyme immunoassay kit; electrogastrograms were performed for 50 min before and after a standardized 10-min meal containing 265 kcal. RESULTS: There were no significant differences in plasma acylated ghrelin levels between healthy volunteers and patients with functional dyspepsia. However, in patients with functional dyspepsia, there was a negative correlation between fasting plasma acylated ghrelin levels and the sum score of epigastric pain (r = -0.427, P = 0.047) and a positive correlation between the postprandial/fasting plasma acylated ghrelin ratio and the sum score of early satiety (r = 0.428, P =0.047). Additionally, there was a negative correlation between fasting acylated ghrelin plasma levels and fasting normogastria (%) (r = -0.522, P = 0.013). Interestingly, two functional dyspepsia patients showed paradoxically elevated plasma acylated ghrelin levels after the meal. CONCLUSION: Abnormal plasma acylated ghrelin levels before or after a meal may be related to several of the dyspeptic symptoms seen in patients with functional dyspepsia. PMID:22611317

DNA damage and plasma homocysteine levels are associated with ...

African Journals Online (AJOL)

This study describes the association between levels of DNA damage and homocysteine (Hcy) in persistent diarrheic (PD) patients and correlates them with serum biochemical metabolites and mineral components. PD patients (n = 36) age 4 - 6 years from Faisalabad hospitals were examined for anthropometric factors, ...

Measurement of plasma 11-deoxycorticosterone levels by radioimmunoassay in man

International Nuclear Information System (INIS)

Fukuchi, Soitsu; Nakajima, Katsuo; Takenouchi, Takahiko; Nishisato, Koji

1974-01-01

A radioimmunoassay procedure has been developed to measure 11-deoxycorticosterone (DOC) in human peripheral plasma. DOC-oxime was coupled with porcine gamma globulin and antibodies produced in rabbits. One to 3 ml of plasma, with 1, 2 3 H-DOC added for recovery, was extracted with dichloromethane and purification achieved by a silica gel column and by one paper chromatograph. After overnight incubation of the antibody-steroid mixture at 4 0 C, bound and free fractions were separated using ammonium sulfate. The mean recovery of 3 H-DOC, after extraction and chromatography, was 84.6 +- 7.4%. The method showed adequate specificity, precision and accuracy. Normal plasma DOC levels were found to be 4.4 +- 2.5 ng/100 ml (n=8). Plasma DOC levels were almost normal (0.3 - 26.8 ng/100 ml) in fifteen patients with benign essential hypertension. The mean level of 8.1 +- 8.2 ng/100 ml obtained in hypertensive patients with suppressed plasma renin activity, was not significantly different from normal. Plasma DOC showed a high level, 3.0 - 30.5 (11.4 +- 7.5) ng/100 ml, in 9 patients with primary aldosteronism. Four out of 8 patients with Cushing's syndrome were found to have elevated plasma DOC levels. Higher levels of 21.2 +- 15.8 ng/100 ml were found in 5 patients with adrenal hyperplasia than those of 12.3 +- 8.0 ng/100 ml in 3 with adrenal adenoma. Plasma DOC levels were high, 113 - 176 ng/100 ml, in 2 patients with 17α-hydroxylase deficiency. ACTH administered to 5 subjects produced a mean increase in plasma DOC from 4.8 to 25.8 ng/100 ml. Angiotensin II infused at a rate of 10 ng/kg/min for 30 min into 4 subjects did not increase mean plasma DOC. Similarly, dietary sodium restriction or postural change did not increase plasma DOC. (auth.)

Impact of Hymenoptera venom allergy and the effects of specific venom immunotherapy on mast cell metabolites in sensitized children

Directory of Open Access Journals (Sweden)

Ewa Cichocka-Jarosz

2014-06-01

Full Text Available introduction and objective. Mast cells (MC are effector cells during severe systemic reactions (SR to Hymenoptera stings. Venom specific immunotherapy (VIT is the treatment of choice for prevention of SR to stings. Tryptase and prostaglandin D[sub]2[/sub] metabolites (PGD[sub]2[/sub] are the markers of MC activation. The study design was to 1. compare baseline values of serum tryptase concentration (BST and PGD[sub]2[/sub] metabolites in children with/without venom sensitization, 2. to evaluate an influence of rush VIT on MC markers in treated children. materials and methods. Sensitized group: 25 children with SR to Hymenoptera sting. Control group: 19 healthy children. Active treatment: 5-day-rush-VIT. BST was evaluated by ImmunoCAP, PGD[sub]2[/sub] metabolites in blood and urine by GC-NICI-MS. results. The baseline blood levels of MC markers were significantly higher, while urinary concentration of 9α,11β-PGF2 was significantly lower in the whole group of venom-sensitized children compared to controls. Severity of SR showed negative correlation with urinary PGD[sub]2[/sub] metabolites, while positive with plasma 9α,11β-PGF2 and BST concentration The highest sensitivity was obtained for plasma 9α,11β-PGF2 whereas the highest specificity for urinary PGD-M. conclusions. In children with IgE-mediated SR to Hymenoptera stings, elevation of baseline values of PGD2 metabolites in blood is accompanied by decreased excretion of its urinary metabolites. Assessment of stable PGD[sub]2 [/sub] metabolites might serve as an independent MC marker to identify allergic children. There is an association between urinary PGD[sub]2[/sub] metabolites and severity of the SR to Hymenoptera stings.

Fully Automated Trimethylsilyl (TMS) Derivatisation Protocol for Metabolite Profiling by GC-MS.

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Zarate, Erica; Boyle, Veronica; Rupprecht, Udo; Green, Saras; Villas-Boas, Silas G; Baker, Philip; Pinu, Farhana R

2016-12-29

Gas Chromatography-Mass Spectrometry (GC-MS) has long been used for metabolite profiling of a wide range of biological samples. Many derivatisation protocols are already available and among these, trimethylsilyl (TMS) derivatisation is one of the most widely used in metabolomics. However, most TMS methods rely on off-line derivatisation prior to GC-MS analysis. In the case of manual off-line TMS derivatisation, the derivative created is unstable, so reduction in recoveries occurs over time. Thus, derivatisation is carried out in small batches. Here, we present a fully automated TMS derivatisation protocol using robotic autosamplers and we also evaluate a commercial software, Maestro available from Gerstel GmbH. Because of automation, there was no waiting time of derivatised samples on the autosamplers, thus reducing degradation of unstable metabolites. Moreover, this method allowed us to overlap samples and improved throughputs. We compared data obtained from both manual and automated TMS methods performed on three different matrices, including standard mix, wine, and plasma samples. The automated TMS method showed better reproducibility and higher peak intensity for most of the identified metabolites than the manual derivatisation method. We also validated the automated method using 114 quality control plasma samples. Additionally, we showed that this online method was highly reproducible for most of the metabolites detected and identified (RSD TMS method has been applied to analyse a large number of complex plasma samples. Furthermore, we found that this method was highly applicable for routine metabolite profiling (both targeted and untargeted) in any metabolomics laboratory.

Plasma catecholamine metabolites in schizophrenics: evidence for the two-subtype concept.

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Chang, W H; Chen, T Y; Lin, S K; Lung, F W; Lin, W L; Hu, W H; Yeh, E K

1990-03-01

Plasma homovanillic acid (pHVA) and plasma methoxyhydroxyphenyl glycol (pMHPG), as well as plasma haloperidol, were measured in 33 schizophrenic patients before and during 6 weeks of haloperidol treatment. Good responders had higher baseline pHVA values compared with poor responders (17.4 +/- 8.8 ng/ml, n = 22 versus 11.4 +/- 5.0 ng/ml, n = 11, p less than 0.05). A higher than 15 ng/ml pretreatment pHVA level was associated with a more consistent clinical response to the subsequent treatment. Differential pHVA changes during treatment were also found between good and poor responders. Within the good responder group, a significant decline in pHVA over time was found. By contrast, pHVA showed a transient increase in the poor responder group. Plasma MHPG changes showed a similar pattern during treatment in good responders, although no significant differences in baseline values were found between the good (n = 13) and poor (n = 9) responders, and pMHPG showed no change during treatment in poor responders. Significant correlations between baseline pHVA and pMHPG values were found in 22 patients. Good responders and poor responders did not differ significantly in terms of age, duration of illness, severity of presenting symptoms, haloperidol dose, or plasma drug concentration. Two hypothetical subtypes of schizophrenia and both dopamine and norepinephrine systems involved in schizophrenic psychopathology are proposed.

Further studies on the plasma biochemistry of the african giant rat ...

African Journals Online (AJOL)

Blood samples collected from the orbital sinus of sixteen mature immature male and female African giant rats were analyzed for the levels of some enzyme and metabolite of nine of their plasma. The alkaline phosphate (ALP) level in the immature group was significantly higher (P < 0.05) than that of male the group. In the ...

Phthalate metabolites in Norwegian mothers and children: Levels, diurnal variation and use of personal care products.

Science.gov (United States)

Sakhi, Amrit Kaur; Sabaredzovic, Azemira; Cequier, Enrique; Thomsen, Cathrine

2017-12-01

Exposure to phthalates has been associated with reproductive and developmental toxicity. Data on levels of these compounds in the Norwegian population is limited. In this study, urine samples were collected from 48 mothers and their children in two counties in Norway. Eleven different phthalate metabolites originating from six commonly used phthalates in consumer products were determined. Concentrations of phthalate metabolites were significantly higher in children compared to mothers except for mono-ethyl phthalate (MEP). The mothers provided several urine samples during 24hours (h) and diurnal variation showed that the concentrations in the morning urine samples (24-8h) were significantly higher than at other time-periods for most of the phthalate metabolites. Intraclass correlation coefficients (ICCs) for 24-hour time-period were in the range of 0.49-0.81. These moderate to high ICCs indicate that one spot urine sample can be used to estimate the exposure to phthalates. Since a significant effect of time of day was observed, it is still advisable to standardize the collection time point to reduce the variation. For the mothers, the use of personal care products (PCPs) were less associated with morning urine samples than early day (8-12h) and evening (16-24h) urine samples. The use of perfume and hair products were positively associated with the urinary concentrations of low molecular weight phthalates. Use of shower soap and shampoo were positively associated with urinary concentration of di(2-ethylhexyl) phthalate (DEHP) metabolites. For children, face cream use was positively associated with phthalate metabolites in the morning samples, and hand soap use was negatively associated with concentration of urinary DEHP metabolites in afternoon/evening samples. Since different PCPs were associated with the urinary phthalate metabolites in different time-periods during a day, more than one spot urine sample might be required to study associations between urinary

GC-MS-Based Metabolome and Metabolite Regulation in Serum-Resistant Streptococcus agalactiae.

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Wang, Zhe; Li, Min-Yi; Peng, Bo; Cheng, Zhi-Xue; Li, Hui; Peng, Xuan-Xian

2016-07-01

Streptococcus agalactiae causes severe systemic infections in human and fish. In the present study, we established a pathogen-plasma interaction model by which we explored how S. agalactiae evaded serum-mediated killing. We found that S. agalactiae grew faster in the presence of yellow grouper plasma than in the absence of the plasma, indicating S. agalactiae evolved a way of evading the fish immune system. To determine the events underlying this phenotype, we applied GC-MS-based metabolomics approaches to identify differential metabolomes between S. agalactiae cultured with and without yellow grouper plasma. Through bioinformatics analysis, decreased malic acid and increased adenosine were identified as the most crucial metabolites that distinguish the two groups. Meanwhile, they presented with decreased TCA cycle and elevated purine metabolism, respectively. Finally, exogenous malic acid and adenosine were used to reprogram the plasma-resistant metabolome, leading to elevated and decreased susceptibility to the plasma, respectively. Therefore, our findings reveal for the first time that S. agalactiae utilizes a metabolic trick to respond to plasma killing as a result of serum resistance, which may be reverted or enhanced by exogenous malic acid and adenosine, respectively, suggesting that the metabolic trick can be regulated by metabolites.

Global metabolomic analysis of human saliva and plasma from healthy and diabetic subjects, with and without periodontal disease.

Directory of Open Access Journals (Sweden)

Virginia M Barnes

Full Text Available Recent studies suggest that periodontal disease and type 2 diabetes mellitus are bi-directionally associated. Identification of a molecular signature for periodontitis using unbiased metabolic profiling could allow identification of biomarkers to assist in the diagnosis and monitoring of both diabetes and periodontal disease. This cross-sectional study identified plasma and salivary metabolic products associated with periodontitis and/or diabetes in order to discover biomarkers that may differentiate or demonstrate an interaction of these diseases. Saliva and plasma samples were analyzed from 161 diabetic and non-diabetic human subjects with a healthy periodontium, gingivitis and periodontitis. Metabolite profiling was performed using Metabolon's platform technology. A total of 772 metabolites were found in plasma and 475 in saliva. Diabetics had significantly higher levels of glucose and α-hydroxybutyrate, the established markers of diabetes, for all periodontal groups of subjects. Comparison of healthy, gingivitis and periodontitis saliva samples within the non-diabetic group confirmed findings from previous studies that included increased levels of markers of cellular energetic stress, increased purine degradation and glutathione metabolism through increased levels of oxidized glutathione and cysteine-glutathione disulfide, markers of oxidative stress, including increased purine degradation metabolites (e.g. guanosine and inosine, increased amino acid levels suggesting protein degradation, and increased ω-3 (docosapentaenoate and ω-6 fatty acid (linoleate and arachidonate signatures. Differences in saliva between diabetic and non-diabetic cohorts showed altered signatures of carbohydrate, lipid and oxidative stress exist in the diabetic samples. Global untargeted metabolic profiling of human saliva in diabetics replicated the metabolite signature of periodontal disease progression in non-diabetic patients and revealed unique metabolic

Association of plasma manganese levels with chronic renal failure.

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Sánchez-González, Cristina; López-Chaves, Carlos; Gómez-Aracena, Jorge; Galindo, Pilar; Aranda, Pilar; Llopis, Juan

2015-01-01

Manganese (Mn) is an essential trace element involved in the formation of bone and in amino acid, lipid and carbohydrate metabolism. Mn excess may be neurotoxic to humans, affecting specific areas of the central nervous system. However, relatively little is known about its physiological and/or toxicological effects, and very few data are available concerning the role of Mn in chronic renal failure (CRF). This paper describes a 12-month study of the evolution of plasma Mn levels in predialysis patients with CRF and the relationship with energy and macronutrient intake. The participants in this trial were 64 patients with CRF in predialysis and 62 healthy controls. Plasma levels of creatinine, urea, uric acid, total protein and Mn were measured. The glomerular filtration rate (GFR) was calculated using the Cockcroft-Gault index. The CRF patients had higher plasma levels of creatinine, urea, uric acid and Mn and a lower GFR than the controls. Plasma Mn was positively correlated with creatinine, plasma urea and plasma uric acid and was negatively correlated with the GFR and the intake of energy and macronutrients. In conclusion, CRF in predialysis patients is associated with increases in circulating levels of Mn. Copyright © 2015 Elsevier GmbH. All rights reserved.

Fibroblast Growth Factor 23 Levels Associate with AKI and Death in Critical Illness.

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Leaf, David E; Jacob, Kirolos A; Srivastava, Anand; Chen, Margaret E; Christov, Marta; Jüppner, Harald; Sabbisetti, Venkata S; Martin, Aline; Wolf, Myles; Waikar, Sushrut S

2017-06-01

Elevated plasma levels of the osteocyte-derived hormone fibroblast growth factor 23 (FGF23) have emerged as a powerful biomarker of cardiovascular disease and death in patients with CKD. Whether elevated urinary or plasma FGF23 levels are prospectively associated with AKI and death in critically ill patients is unknown. We therefore conducted a prospective cohort study of 350 critically ill patients admitted to intensive care units at an academic medical center to investigate whether higher urinary FGF23 levels associate with the composite end point of AKI or in-hospital mortality (AKI/death). We measured urinary FGF23 levels within 24 hours of admission to the intensive care unit. In a subcohort ( n =131) we also measured plasma levels of FGF23, calcium, phosphate, parathyroid hormone, and vitamin D metabolites. Urinary and plasma FGF23 levels, but not other mineral metabolites, significantly associated with AKI/death. In multivariate analyses, patients in the highest compared with the lowest quartile of urinary FGF23 had a 3.9 greater odds (95% confidence interval, 1.6 to 9.5) of AKI/death. Higher urinary FGF23 levels also independently associated with greater hospital, 90-day, and 1-year mortality; longer length of stay; and several other important adverse outcomes. In conclusion, elevated FGF23 levels measured in the urine or plasma may be a promising novel biomarker of AKI, death, and other adverse outcomes in critically ill patients. Copyright © 2017 by the American Society of Nephrology.

An integrated strategy for in vivo metabolite profiling using high-resolution mass spectrometry based data processing techniques

International Nuclear Information System (INIS)

Guo, Jian; Zhang, Minli; Elmore, Charles S.; Vishwanathan, Karthick

2013-01-01

Graphical abstract: -- Highlights: •Profiling the metabolites of model compounds in rats using high resolution mass spectrometry based data processing techniques. •Demonstrating an integrated strategy in vivo metabolite profiling using data mining tools. •Unusual metabolites generated via thiazole-ring opening were characterized based on processed LC–MS.data. -- Abstract: An ongoing challenge of drug metabolite profiling is to detect and identify unknown or low-level metabolites in complex biological matrices. Here we present a generic strategy for metabolite detection using multiple accurate-mass-based data processing tools via the analysis of rat samples of two model drug candidates, AZD6280 and AZ12488024. First, the function of isotopic pattern recognition was proved to be highly effective in the detection of metabolites derived from [ 14 C]-AZD6280 that possesses a distinct isotopic pattern. The metabolites revealed using this approach were in excellent qualitative correlation to those observed in radiochromatograms. Second, the effectiveness of accurate mass based untargeted data mining tools such as background subtraction, mass defect filtering, or a data mining package (MZmine) used for metabolomic analysis in detection of metabolites of [ 14 C]-AZ12488024 in rat urine, feces, bile and plasma samples was examined and a total of 33 metabolites of AZ12488024 were detected. Among them, at least 16 metabolites were only detected by the aid of the data mining packages and not via radiochromatograms. New metabolic pathways such as S-oxidation and thiomethylation reactions occurring on the thiazole ring were proposed based on the processed data. The results of these experiments also demonstrated that accurate mass-based mass defect filtering (MDF) and data mining techniques used in metabolomics are complementary and can be valuable tools for delineating low-level metabolites in complex matrices. Furthermore, the application of distinct multiple data

The measurement of acetanilide in plasma by spectrophotometric and selected ion monitoring methods.

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Baty, J D; Playfer, J; Evans, D A; Lamb, J

1977-08-01

Plasma samples from volunteers who had received an oral dose of acetanilide have been analysed by gas chromatography mass spectrometry and ultraviolet absorption techniques. The gas chromatography mass spectrometry method involved extraction of the plasma and analysis of the acetanilide using selected ion monitoring with a deuterated internal standard. In the ultraviolet method the plasma was hydrolysed with acid to convert the acetanilide to aniline, and this compound was diazotized and coupled with N-1-naphthylethylene-diamine. The absorbance of the resulting complex was read at 550 nm. Acetanilide levels in plasma determined by the selected ion monitoring method were significantly lower than those measured by spectrophotometry. Pharmacokinetic data calculated from the results obtained using these two assays are very different and illustrate the need for an accurate and specific method of analysis. The major metabolites of acetanilide are shown not to interfere with these assays and the results suggest the possible presence of a new metabolite of acetanilide.

Determination of vitamins D2, D3, K1 and K3 and some hydroxy metabolites of vitamin D3 in plasma using a continuous clean-up-preconcentration procedure coupled on-line with liquid chromatography-UV detection.

Science.gov (United States)

Ortiz Boyer, F; Fernández Romero, J M; Luque de Castro, M D; Quesada, J M

1999-03-01

A semi-automatic procedure for the continuous clean-up and concentration of several fat-soluble vitamins prior to their separation by HPLC and UV detection is reported. The procedure is based on the use of a minicolumn packed with aminopropylsilica as sorbent located prior to the chromatographic detection system. The overall process was developed and applied to the main liposoluble vitamins (A, D2, D3, E, K1, K3) and several hydroxy metabolites of vitamin D3 [25-(OH)-D3,24,25-(OH)2-D3 and 1,25-(OH)2-D3]. All the analytes were monitored at a compromise wavelength of 270 nm. Calibration graphs were constructed between 0.01 and 100 ng ml-1 for vitamin D2 and D3 and their hydroxy metabolites, between 0.1 and 100 ng ml-1 for vitamin A, K1 and K3 and between 1 and 100 ng ml-1 for vitamin E, with excellent regression coefficients (> or = 0.9901) in all cases. The precision was established at two concentration levels with acceptable RSDs in all instances (between 3.6 and 8.7%). The method was appropriate for the determination of vitamin D2, D3, K1 and K3 and the 24,25-dihydroxy and 25-hydroxy metabolites of vitamin D3 in human plasma. The method was applied to plasma samples spiked with the target analytes and the recoveries ranged between 78 and 109%.

Simultaneous quantification of PGI2 and TXA2 metabolites in plasma and urine in NO-deficient mice by a novel UHPLC/MS/MS method.

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Kij, Agnieszka; Mateuszuk, Lukasz; Sitek, Barbara; Przyborowski, Kamil; Zakrzewska, Agnieszka; Wandzel, Krystyna; Walczak, Maria; Chlopicki, Stefan

2016-09-10

The balance between vascular prostacyclin (PGI2) generated mainly via cyclooxygenase-2 (COX-2) and its physiological antagonist platelet-derived thromboxane A2 (TXA2) formed by cyclooxygenase-1 (COX-1) determines cardiovascular homeostasis. In the present work, a novel bioanalytical method for simultaneous quantification of stable plasma and urinary metabolites of PGI2 (6-keto-PGF1α, 2,3-dinor-6-keto-PGF1α) and TXA2 (TXB2, 2,3-dinor-TXB2) using ultra high-performance liquid chromatography coupled with tandem mass spectrometry (UHPLC/MS/MS) was developed. The method was validated using artificial plasma and urine and linearity range, intra- and inter-day precision and accuracy, recovery of analytes, relative and absolute matrix effect and stability of analytes were determined. The use of artificial biofluids improved the method sensitivity as it eliminated the contribution of endogenous metabolites present in mice plasma and urine to validation procedure. The newly developed and validated method allowed to quantify 6-keto-PGF1α and TXB2 in mice plasma as well as 2,3-dinor-6-keto-PGF1α and 2,3-dinor-TXB2 in urine samples with high sensitivity and accuracy. The calibration range was established from 0.1 to 100ng/mL for all analytes using artificial biofluids and the recoveries were greater than 89.9%. All validated parameters met the criteria of acceptance specified in FDA and EMA guidance. This method was successfully employed for profiling of the changes in PGI2 and TXA2 generation in NO-deficient mice. This work demonstrated that NO-deficiency induced by L-NAME, evidenced by a fall in nitrite in plasma and urine, was associated with platelet activation, robust increase in TXB2 and mild increase in 6-keto-PGF1α concentration in plasma. Changes in 2,3-dinor-6-keto-PGF1α and 2,3-dinor-TXB2 concentration in urine were less evident suggesting that the measurements in plasma better reflect modest changes in PGI2/TXA2 homeostasis than measurements in urine

Pharmacokinetics of tramadol hydrochloride and its metabolite O-desmethyltramadol in peafowl (Pavo cristatus).

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Black, Peter A; Cox, Sherry K; Macek, Michael; Tieber, Anne; Junge, Randall E

2010-12-01

Tramadol is a centrally acting opiate analgesic that has not been well studied in avian species. Tramadol and its metabolites exert their effects at multiple sites, including opiate (mu, kappa, and delta), adrenergic (alpha-2), and serotonin (5HT) receptors. This multi-receptor mode of action is advantageous for avian patients because the mechanisms for analgesia have not been fully elucidated in all species. The objective of this study was to document the pharmacokinetics of tramadol and its active metabolite O-desmethyltramadol (M1) in common peafowl (Pavo cristatus). Based on results from a pilot animal, six adult peafowl (three male, three female) judged to be clinically healthy based on physical exam and routine bloodwork were selected for this study. Each bird was anesthetized for placement of a jugular catheter, and 7.5 mg/kg tramadol was administered orally via gavage tube. Blood samples were collected just prior to drug administration; at 30 min; and at 1, 2, 3, 4, 6, 8, 10, 12, 24, and 34 hr. Plasma levels of tramadol and M1 were measured and the pharmacokinetics for each drug was calculated. Although tramadol was quickly metabolized, plasma levels of M1 remained at or near human analgesic levels for 12-24 hr. Based on these data, tramadol may be a practical option as an orally administered analgesic agent in avian patients. Further studies, including antinociceptive studies, are needed.

A liquid chromatography with tandem mass spectrometry method for simultaneous determination of UTL-5g and its metabolites in human plasma.

Science.gov (United States)

Shaw, Jiajiu; Wiegand, Richard; Wu, Jianmei; Bao, Xun; Valeriote, Frederick; Li, Jing

2015-06-01

UTL-5g is a novel small-molecule TNF-α inhibitor under investigation as both a chemoprotective and radioprotective agent. Animal studies showed that pretreatment of UTL-5g protected kidney, liver, and platelets from cisplatin-induced toxicity. In addition, UTL-5g reduced liver and lung injuries induced by radiation in vivo. Although a number of preclinical studies have been conducted, a validated bioanalytical method for UTL-5g in human plasma has not been published. In this work, a sensitive and reproducible reverse-phase liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) assay was developed and validated for the determination of UTL-5g and its metabolites, 5-methylisoxazole-3-carboxylic acid (ISOX) and 2,4-dichloroaniline (DCA), in human plasma. The method involves a simple methanol precipitation step followed by injection of the supernatant onto a Waters 2695 HPLC system coupled with a Waters Quattro Micro™ triple quadrupole mass spectrometer. Chromatographic separation was accomplished using a Waters Nova-Pak C18 column maintained at 30°C, running at gradient mode with mobile phase consisting of 0.1% formic acid in water and 0.1% formic acid in methanol at a flow rate of 0.2mL/min. The analytes were monitored under positive electrospray ionization (ESI). Quantitation of these compounds in plasma was linear from 0.05 to 10μM. The lower limit of quantitation (LLOQ) was 0.05, 0.1, and 0.2μM for UTL-5g, ISOX and DCA, respectively. The accuracy and intra-and inter-day precisions were within the generally accepted criteria for bioanalytical method (5g and its metabolites, ISOX and DCA. Copyright © 2015 Elsevier B.V. All rights reserved.

Plasma lactoferrin levels in pregnancy and cystic fibrosis

International Nuclear Information System (INIS)

Sykes, J.A.C.; Thomas, M.J.; Goldie, D.J.; Turner, G.M.

1982-01-01

Plasma lactoferrin levels have been determined by radioimmunoassay for the different weeks of normal pregnancy, in normal healthy adults and in children with and without cystic fibrosis. The lactoferrin levels were higher in pregnancy than in both male and female normal adults and showed a slight progressive increase up to week 29 and thereafter remained high. Five out of seven children with cystic fibrosis had markedly raised plasma lactoferrin levels from six to 16 times higher than the mean of a control group of children. (Auth.)

Intestinal Microbiota-Derived Metabolomic Blood Plasma Markers for Prior Radiation Injury

International Nuclear Information System (INIS)

Ó Broin, Pilib; Vaitheesvaran, Bhavapriya; Saha, Subhrajit; Hartil, Kirsten; Chen, Emily I.; Goldman, Devorah; Fleming, William Harv; Kurland, Irwin J.; Guha, Chandan; Golden, Aaron

2015-01-01

Purpose: Assessing whole-body radiation injury and absorbed dose is essential for remediation efforts following accidental or deliberate exposure in medical, industrial, military, or terrorist incidents. We hypothesize that variations in specific metabolite concentrations extracted from blood plasma would correlate with whole-body radiation injury and dose. Methods and Materials: Groups of C57BL/6 mice (n=12 per group) were exposed to 0, 2, 4, 8, and 10.4 Gy of whole-body gamma radiation. At 24 hours after treatment, all animals were euthanized, and both plasma and liver biopsy samples were obtained, the latter being used to identify a distinct hepatic radiation injury response within plasma. A semiquantitative, untargeted metabolite/lipid profile was developed using gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry, which identified 354 biochemical compounds. A second set of C57BL/6 mice (n=6 per group) were used to assess a subset of identified plasma markers beyond 24 hours. Results: We identified a cohort of 37 biochemical compounds in plasma that yielded the optimal separation of the irradiated sample groups, with the most correlated metabolites associated with pyrimidine (positively correlated) and tryptophan (negatively correlated) metabolism. The latter were predominantly associated with indole compounds, and there was evidence that these were also correlated between liver and plasma. No evidence of saturation as a function of dose was observed, as has been noted for studies involving metabolite analysis of urine. Conclusions: Plasma profiling of specific metabolites related to pyrimidine and tryptophan pathways can be used to differentiate whole-body radiation injury and dose response. As the tryptophan-associated indole compounds have their origin in the intestinal microbiome and subsequently the liver, these metabolites particularly represent an attractive marker for radiation injury within blood plasma

Intestinal Microbiota-Derived Metabolomic Blood Plasma Markers for Prior Radiation Injury

Energy Technology Data Exchange (ETDEWEB)

Ó Broin, Pilib [Department of Genetics, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York (United States); Department of Mathematical Sciences, Yeshiva University, New York, New York (United States); Vaitheesvaran, Bhavapriya [Department of Medicine, Diabetes Center, Stable Isotope and Metabolomics Core Facility, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York (United States); Saha, Subhrajit [Department of Radiation Oncology, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York (United States); Hartil, Kirsten [Department of Medicine, Diabetes Center, Stable Isotope and Metabolomics Core Facility, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York (United States); Chen, Emily I. [Department of Pharmacology, Proteomics Shared Resource, Herbert Irving Comprehensive Cancer Center, Columbia University Medical Center, New York, New York (United States); Goldman, Devorah; Fleming, William Harv [Department of Medicine, Oregon Health and Science University, Portland, Oregon (United States); Kurland, Irwin J. [Department of Medicine, Diabetes Center, Stable Isotope and Metabolomics Core Facility, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York (United States); Guha, Chandan, E-mail: cguha@montefiore.org [Department of Radiation Oncology, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York (United States); Golden, Aaron, E-mail: aaron.golden@einstein.yu.edu [Department of Genetics, Albert Einstein College of Medicine of Yeshiva University, Bronx, New York (United States); Department of Mathematical Sciences, Yeshiva University, New York, New York (United States)

2015-02-01

Purpose: Assessing whole-body radiation injury and absorbed dose is essential for remediation efforts following accidental or deliberate exposure in medical, industrial, military, or terrorist incidents. We hypothesize that variations in specific metabolite concentrations extracted from blood plasma would correlate with whole-body radiation injury and dose. Methods and Materials: Groups of C57BL/6 mice (n=12 per group) were exposed to 0, 2, 4, 8, and 10.4 Gy of whole-body gamma radiation. At 24 hours after treatment, all animals were euthanized, and both plasma and liver biopsy samples were obtained, the latter being used to identify a distinct hepatic radiation injury response within plasma. A semiquantitative, untargeted metabolite/lipid profile was developed using gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry, which identified 354 biochemical compounds. A second set of C57BL/6 mice (n=6 per group) were used to assess a subset of identified plasma markers beyond 24 hours. Results: We identified a cohort of 37 biochemical compounds in plasma that yielded the optimal separation of the irradiated sample groups, with the most correlated metabolites associated with pyrimidine (positively correlated) and tryptophan (negatively correlated) metabolism. The latter were predominantly associated with indole compounds, and there was evidence that these were also correlated between liver and plasma. No evidence of saturation as a function of dose was observed, as has been noted for studies involving metabolite analysis of urine. Conclusions: Plasma profiling of specific metabolites related to pyrimidine and tryptophan pathways can be used to differentiate whole-body radiation injury and dose response. As the tryptophan-associated indole compounds have their origin in the intestinal microbiome and subsequently the liver, these metabolites particularly represent an attractive marker for radiation injury within blood plasma.

Intestinal microbiota-derived metabolomic blood plasma markers for prior radiation injury.

Science.gov (United States)

Ó Broin, Pilib; Vaitheesvaran, Bhavapriya; Saha, Subhrajit; Hartil, Kirsten; Chen, Emily I; Goldman, Devorah; Fleming, William Harv; Kurland, Irwin J; Guha, Chandan; Golden, Aaron

2015-02-01

Assessing whole-body radiation injury and absorbed dose is essential for remediation efforts following accidental or deliberate exposure in medical, industrial, military, or terrorist incidents. We hypothesize that variations in specific metabolite concentrations extracted from blood plasma would correlate with whole-body radiation injury and dose. Groups of C57BL/6 mice (n=12 per group) were exposed to 0, 2, 4, 8, and 10.4 Gy of whole-body gamma radiation. At 24 hours after treatment, all animals were euthanized, and both plasma and liver biopsy samples were obtained, the latter being used to identify a distinct hepatic radiation injury response within plasma. A semiquantitative, untargeted metabolite/lipid profile was developed using gas chromatography-mass spectrometry and liquid chromatography-tandem mass spectrometry, which identified 354 biochemical compounds. A second set of C57BL/6 mice (n=6 per group) were used to assess a subset of identified plasma markers beyond 24 hours. We identified a cohort of 37 biochemical compounds in plasma that yielded the optimal separation of the irradiated sample groups, with the most correlated metabolites associated with pyrimidine (positively correlated) and tryptophan (negatively correlated) metabolism. The latter were predominantly associated with indole compounds, and there was evidence that these were also correlated between liver and plasma. No evidence of saturation as a function of dose was observed, as has been noted for studies involving metabolite analysis of urine. Plasma profiling of specific metabolites related to pyrimidine and tryptophan pathways can be used to differentiate whole-body radiation injury and dose response. As the tryptophan-associated indole compounds have their origin in the intestinal microbiome and subsequently the liver, these metabolites particularly represent an attractive marker for radiation injury within blood plasma. Copyright © 2015 Elsevier Inc. All rights reserved.

Plasma homovanillic acid in schizophrenics: supportive evidence for the two-subtype hypothesis.

Science.gov (United States)

Chen, T Y; Lee, C F; Lung, F W; Lee, T C; Lin, W L; Hu, W H; Yeh, E K; Chang, W H

1989-06-01

Plasma levels of homovanillic acid (pHVA), a major metabolite of dopamine (DA), were measured in a group of 51 schizophrenic inpatients before and during 6 weeks of neuroleptic treatment. Steady-state plasma drug concentrations were monitored in parallel with pHVA. Good responders (n = 22) had higher pretreatment pHVA levels as compared to poor responders (n = 22). Differential pHVA changes during neuroleptic treatment were also found between each group. The two groups did not differ significantly in terms of age, duration of illness, severity of presenting symptoms, neuroleptic, dose, or plasma drug concentration. Two hypothetical subtypes in the group of schizophrenics were proposed.

Comparative plasma disposition kinetics of albendazole and its new benzimidazol prodrug in dog.

Science.gov (United States)

Khalil, Z; El Karbane, M; Faouzi, M E A; Ansar, M; Azougagh, M; El Harti, J; Taoufik, J

2016-01-01

The comparative pharmacokinetic behavior of albendazole (ABZ) and its new benzimidazol prodrug [1-tert-butyloxycarbonyl-5-propylthio-1-H-benzimidazol-2ylcarbamate of methyl] (ABZBoc), following their oral administration (10mg/kg) to healthy dogs was explored. Blood samples were obtained serially over a 24h period after treatment, then the plasma was analyzed by high-performance liquid chromatography (HPLC) to search the albendazole metabolites (ABZSO and ABZSO2). However, the albendazole parent drug was not detectable at any time after both treatments (ABZ and ABZBoc). By albendazole metabolites (ABZSO and ABZSO2) were the analytes recovered in the plasma after oral administration of ABZ and ABZBoc. Furthermore, some amounts of ABZBoc were also available in the plasma samples treated with this new produg. The plasma profile of each analyte followed a similar pattern after both treatments, the active metabolite (ABZSO) was the major analyte recovered in plasma (between 1 and 24h post-treatment). The pharmacokinetic parameters of both groups were calculated (Cmax, Tmax, t1/2, AUC0-›∞), and analyzed using the Student's t-test, Palbendazole metabolites (ABZSO, ABZSO2) between the group treated with albendazole (group A) and that treated with ABZBoc prodrug (group B). Hence, the levels of the various pharmacokinetics parameters were low in the group treated with prodrug, as well they did not reach equivalent concentrations to that of albendazole. These differences between albendazole and its new prodrug may be explained by the fact that ABZBoc prodrug was not effectively reduced in the intestine of dogs. Copyright © 2015 Académie Nationale de Pharmacie. Published by Elsevier Masson SAS. All rights reserved.

Levels of infants' urinary arsenic metabolites related to formula feeding and weaning with rice products exceeding the EU inorganic arsenic standard.

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Antonio J Signes-Pastor

Full Text Available Early childhood inorganic arsenic (i-As exposure is of particular concern since it may adversely impact on lifetime health outcomes. Infants' urinary arsenic (As metabolites were analysed in 79 infants by inductively coupled plasma-mass spectrometric detection (IC-ICP-MS to evaluate i-As exposure pre- and post-weaning. Levels of i-As in rice-based weaning and infants' foods were also determined to relate to urinary As levels. Higher As levels, especially of monomethylarsonic acid (MMA and dimethylarsinic acid (DMA, were found in urine from formula fed infants compared to those breastfed. Urine from infants post-weaning consuming rice-products resulted in higher urinary MMA and DMA compared to the paired pre-weaning urine samples. The European Union (EU has regulated i-As in rice since 1st January 2016. Comparing infants' rice-based foods before and after this date, little change was found. Nearly ¾ of the rice-based products specifically marketed for infants and young children contained i-As over the 0.1 mg/kg EU limit. Efforts should be made to provide low i-As rice and rice-based products consumed by infants and young children that do not exceed the maximum i-As level to protect this vulnerable subpopulation.

Glyoxylate, a New Marker Metabolite of Type 2 Diabetes

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Nikiforova, Victoria J.; Giesbertz, Pieter; Wiemer, Jan; Bethan, Bianca; Looser, Ralf; Liebenberg, Volker; Ruiz Noppinger, Patricia; Daniel, Hannelore; Rein, Dietrich

2014-01-01

Type 2 diabetes (T2D) is characterized by a variety of metabolic impairments that are closely linked to nonenzymatic glycation reactions of proteins and peptides resulting in advanced glycation end-products (AGEs). Reactive aldehydes derived from sugars play an important role in the generation of AGEs. Using metabolite profiling to characterize human plasma from diabetic versus nondiabetic subjects we observed in a recent study that the reactive aldehyde glyoxylate was increased before high levels of plasma glucose, typical for a diabetic condition, could be measured. Following this observation, we explored the relevance of increased glyoxylate in diabetic subjects and in diabetic C57BLKS/J-Leprdb/db−/− mice in the pathophysiology of diabetes. A retrospective study using samples of long-term blood donors revealed that glyoxylate levels unlike glucose levels became significantly elevated up to 3 years prior to diabetes diagnosis (difference to control P = 0.034). Elevated glyoxylate levels impact on newly identified mechanisms linking hyperglycemia and AGE production with diabetes-associated complications such as diabetic nephropathy. Glyoxylate in its metabolic network may serve as an early marker in diabetes diagnosis with predictive qualities for associated complications and as potential to guide the development of new antidiabetic therapies. PMID:25525609

Liquid chromatography-tandem mass spectrometric assay for the simultaneous determination of the irreversible BTK inhibitor ibrutinib and its dihydrodiol-metabolite in plasma and its application in mouse pharmacokinetic studies

NARCIS (Netherlands)

Rood, Johannes J M; van Hoppe, Stephanie; Schinkel, Alfred H.; Schellens, Jan H M; Beijnen, Jos H.; Sparidans, Rolf W.

2016-01-01

A validated simple, fast and sensitive bio-analytical assay for ibrutinib and its dihydrodiol metabolite in human and mouse plasma was set up. Sample preparation was performed by protein precipitation, and addition of the respective deuterated internal standards, followed by LC-MS/MS analysis.

Pavlovian autoshaping procedures increase plasma corticosterone levels in rats.

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Tomie, Arthur; Silberman, Yuval; Williams, Kayon; Pohorecky, Larissa A

2002-06-01

Pavlovian autoshaping conditioned responses (CRs) are complex sequences of conditioned stimulus (CS)-directed skeletal-motor responses that are elicited by CS objects predictive of food unconditioned stimulus (US). Autoshaping CRs are observed under conditions known to be conducive to elevations in plasma corticosterone levels, as, for example, in response to the eating of food as well as in response to signals predictive of food. Two experiments investigated the relationships between Pavlovian autoshaping procedures, the performance of Pavlovian autoshaping CRs, and plasma corticosterone levels in male Long-Evans rats. In Experiment 1, rats in the CS-US paired group (n=30) were given 20 daily sessions of Pavlovian autoshaping training wherein the insertion of a retractable lever CS was followed by the response-independent presentation of the food US. Tail blood samples obtained after the 20th autoshaping session revealed higher plasma corticosterone levels in the CS-US paired group than in the CS-US random control group (n=10). In Experiment 2, rats (n=35) were assessed for basal plasma corticosterone levels 2 weeks prior to autoshaping training. Plasma samples obtained immediately following the first autoshaping session, and prior to the acquisition of lever-press autoshaping CR performance, revealed higher plasma corticosterone levels in the CS-US paired group (n=24) relative to basal levels. This effect was not observed in the CS-US random control group (n=11). Data suggest that corticosterone release is a physiological endocrine Pavlovian CR induced by lever CS-food US pairings during Pavlovian autoshaping procedures, rather than a by-product of autoshaping CR performance. Implications of the link between autoshaping procedures and corticosterone release are discussed.

Effect of medium-chain triglycerides on growth performance, nutrient digestibility, plasma metabolites and antioxidant capacity in weanling pigs

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Yue Li

2015-03-01

Full Text Available The aim of this study was to investigate the effect of medium-chain triglycerides (MCTs on growth performance, nutrient digestibility, plasma metabolites and antioxidant capacity in weanling pigs. A total of 160 weanling (Duroc × Landrace × Yorkshire pigs (age: 21 ± 1 d; body weight: 7.50 ± 0.28 kg were randomly allotted to 4 treatments, receiving the following diets for 28 d: control diet [containing 3.5% soybean oil (SO], MCT1 diet (containing 0.7% MCTs and 2.8% SO, MCT2 diet (containing 1.4% MCTs and 2.1% SO and MCT3 diet (containing 2.1% MCTs and 1.4% SO. Dietary inclusion of MCTs improved the average daily gain and feed efficiency (FE of pigs compared with the control during the first 2 weeks post-weaning (P < 0.05. A similar positive effect was also observed for the overall FE in MCT2 group (P < 0.05. Compared with the control, apparent total tract digestibility (ATTD of ether extract was improved by MCT2 and MCT3 treatment from day 12–14 post-weaning (P < 0.05. In addition, MCT2 treatment also exerted a beneficial effect on the ATTD of dry matter (P < 0.05. The increased total protein concentration and decreased urea nitrogen and malondialdehyde levels of plasma were observed in both MCT2 and MCT3 groups on day 14 post-weaning (P < 0.05. In conclusion, MCTs could improve growth performance, nutrients utilization, and antioxidant ability of weanling piglets.

Comparative kinetics of the turnover rates of vitamin D2 and vitamin D3 and their metabolites in chick plasma

International Nuclear Information System (INIS)

Hoy, D.A.; Horst, R.L.

1986-01-01

Studies regarding the discrimination between vitamin D 2 and vitamin D 3 by chickens have led to conflicting conclusions. To investigate this problem in more detail the authors administered radiolabeled vitamin D and vitamin D metabolites, which allowed them to determine their relative plasma clearance rates. The study involved 3 groups of adult male chickens (5/group). Group I received [ 3 H]-vitamin D 2 (1.2 Ci/mmole) and [ 3 H]-vitamin D 3 (1.2 Ci/mmole). Group II received [ 3 H]-25-OHD 2 (90 Ci/mmole) and [ 3 H]-25-OHD 3 (90 Ci/mmole). Group III received [ 3 H]-1,25-(OH) 2 D 3 (90 Ci/mmole) and [ 3 H]-1,25-(OH) 2 D 2 (90 Ci/mmole). The [ 3 H]-sterols were co-dosed within each group. The results indicated that the turnover rates of [ 3 H]-vitamin D 2 and [ 3 H]-vitamin D 3 were not significantly different. However, the plasma turnover of the 25 hydroxylated metabolites differed, with [ 3 H]-25-OHD 2 clearing faster (2-4X) than [ 3 H]-25-OHD 3 . The largest difference appeared in the 1,25-(OH) 2 D turnover rates with 1,25-(OH) 2 D 2 clearing approximately 10X faster than [ 3 H]-1,25-(OH) 2 D 3 . These data, therefore, indicate that discrimination against vitamin D 2 sterols in the chick occurs primarily between steps in the metabolism of vitamin D and not at the point of the parent vitamin

Comparative plasma disposition of fenbendazole, oxfendazole and albendazole in dogs.

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Gokbulut, C; Bilgili, A; Hanedan, B; McKellar, Q A

2007-09-30

The plasma disposition of fenbendazole (FBZ), oxfendazole (OFZ) and albendazole (ABZ); and the enantiospecific disposition of OFZ, and ABZSO produced were investigated following an oral administration (50 mg/kg) in dogs. Blood samples were collected from 1 to 120 h post-administration. The plasma samples were analysed by high performance liquid chromatography (HPLC). The plasma concentration of FBZ, OFZ, ABZ and their metabolites were significantly different from each other and depended on the drug administered. The sulphone metabolite (FBZSO2) of FBZ was not detected in any plasma samples and the parent molecule ABZ did not reach quantifiable concentrations following FBZ and ABZ administration, respectively. OFZ and its sulphone metabolite attained a significantly higher plasma concentration and remained much longer in plasma compared with FBZ and ABZ and their respective metabolites. The maximum plasma concentrations (Cmax), area under the concentration time curve (AUC) and mean residence time (MRT) of parent OFZ were more than 30, 68 and 2 times those of FBZ, respectively. The same parameters for ABZSO were also significantly greater than those of FBZSO. The ratio for total AUCs of both the parent drug and the metabolites were 1:42:7 for following FBZ, OFZ and ABZ administration, respectively. The enantiomers were never in racemic proportions and (+) enantiomers of both OFZ and ABZSO were predominant in plasma. The AUC of (+) enantiomers of OFZ and ABZSO was, respectively more than three and seven times larger than that of (-) enantiomers of both molecules. It is concluded that the plasma concentration of OFZ was substantially greater compared with FBZ and ABZ. The data on the pharmacokinetic profile of OFZ presented here may contribute to evaluate its potential as an anthelmintic drug for parasite control in dogs.

The observation on plasma endothelin levels in patients with graves' disease

International Nuclear Information System (INIS)

Hao Xiaojun; Liu Changshan; Yang Lianrong; Zhang Qiliang; Wang Honggang; Liu Xudong

2002-01-01

Observing the plasma endothelin levels in patients with Graves' disease to probe its clinical significance, plasma endothelin levels were measured in 55 cases of Graves' disease before and after treatment respectively, and these were compared with that of 23 health subjects. Results: plasma endothelin levels in patients with Graves' disease significantly increase, compared with heath subjects (150.4 +- 29.31 ng/L vs 42.80 +- 7.58 ng/L, P < 0.01); post-treatment endothelin levels apparently decrease (97.61 +- 15.99 ng/L vs 150.4 +- 29.31 ng/L, P < 0.01). Plasma endothelin levels in patients with Graves' disease significantly increase, and after treatment the endothelin levels decrease following decreasing of thyroid hormone level and high hemodynamics

Association of plasma fatty acid composition with plasma irisin levels in normal weight and overweight/obese children.

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Viitasalo, A; Ågren, J; Venäläinen, T; Pihlajamäki, J; Jääskeläinen, J; Korkmaz, A; Atalay, M; Lakka, T A

2016-08-01

Irisin has been suggested to protect against overweight. There are no previous data on the association of plasma fatty acid (FA) composition with plasma irisin. We studied the association of FA composition with plasma irisin in normal weight and overweight/obese children. This cross-sectional study included pre-pubertal children (388 normal weight children and 55 overweight/obese children); 6-9 years of age, taking part in the Physical Activity and Nutrition in Children Study. After an overnight fast, we measured plasma FA composition by gas chromatography and plasma irisin levels by enzyme-linked immunosorbent assay. Higher proportion of total monounsaturated fatty acids in plasma cholesteryl esters (CEs) (β = 0.139, P = 0.003) and phospholipids (PLs) (β = 0.147, P = 0.002) and lower proportion of total polyunsaturated fatty acids in plasma CE (β = -0.130, P = 0.006) and PL (β = -0.165, P overweight/obese children compared to normal weight children. Higher proportion of γ-linolenic acid (β = 0.324, P = 0.017) and lower proportion of linoleic acid (β = -0.397, P = 0.005) in plasma CE were related to higher plasma irisin level among overweight/obese children, indicating the direct association of estimated D6D activity in plasma CE (β = 0.343, P = 0.011) with plasma irisin. Furthermore, higher proportion of oleic acid in plasma CE (β = 0.345, P = 0.012) and PL (β = 0.292, P = 0.033) and higher proportion of adrenic acid (β = 0.366, P = 0.008) and docosapentaenoic acid (β = 0.351, P = 0.010) in plasma PL were associated with higher plasma irisin level among overweight/obese children. Metabolically unfavourable plasma FA profile was associated with higher plasma irisin level especially in overweight/obese children, suggesting that excess body fat might modulate these relationships. © 2015 World Obesity.

Quantitative analyses of schizophrenia-associated metabolites in serum: serum D-lactate levels are negatively correlated with gamma-glutamylcysteine in medicated schizophrenia patients.

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Takeshi Fukushima

Full Text Available The serum levels of several metabolites are significantly altered in schizophrenia patients. In this study, we performed a targeted analysis of 34 candidate metabolites in schizophrenia patients (n = 25 and compared them with those in age- and gender-matched healthy subjects (n = 27. Orthogonal partial least square-discriminant analysis revealed that complete separation between controls and patients was achieved based on these metabolites. We found that the levels of γ-glutamylcysteine (γ-GluCys, linoleic acid, arachidonic acid, D-serine, 3-hydroxybutyrate, glutathione (GSH, 5-hydroxytryptamine, threonine, and tyrosine were significantly lower, while D-lactate, tryptophan, kynurenine, and glutamate levels were significantly higher in schizophrenia patients compared to controls. Using receiver operating characteristics (ROC curve analysis, the sensitivity, specificity, and the area under curve of γ-GluCys, a precursor of GSH, and D-lactate, a terminal metabolite of methylglyoxal, were 88.00%, 81.48%, and 0.8874, and 88.00%, 77.78%, and 0.8415, respectively. In addition, serum levels of D-lactate were negatively correlated with γ-GluCys levels in patients, but not in controls. The present results suggest that oxidative stress-induced damage may be involved in the pathogenesis of schizophrenia.

Increased Plasma Levels of Heme Oxygenase-1 in Human Brucellosis.

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Chen, Zhe; Zhang, Yu-Xue; Fu, Dong-Wei; Gao, Qing-Feng; Ge, Feng-Xia; Liu, Wei-Hua

2016-08-01

Brucellosis is associated with inflammation and the oxidative stress response. Heme oxygenase-1 (HO-1) is a cytoprotective stress-responsive enzyme that has anti-inflammatory and anti-oxidant effects. Nevertheless, the role of HO-1 in human brucellosis has not yet been studied. The aim of this study was to examine the plasma levels of HO-1 in patients with brucellosis and to evaluate the ability of plasma HO-1 levels as an auxiliary diagnosis, a severity predictor, and a monitor for brucellosis treatments. A total of 75 patients with brucellosis were divided into the acute, subacute, chronic active, and chronic stable groups. An additional 20 volunteers were included as the healthy control group. The plasma HO-1 levels and other laboratory parameters were measured in all groups. Furthermore, the plasma levels of HO-1 in the acute group were compared before and after treatment. The plasma HO-1 levels were considerably increased in the acute (4.97 ± 3.55), subacute (4.98 ± 3.23), and chronic active groups (4.43 ± 3.00) with brucellosis compared to the healthy control group (1.03 ± 0.63) (p brucellosis (r = 0.707, p brucellosis status and may be used as a supplementary plasma marker for diagnosing brucellosis and monitoring its treatment.

Quantification of sibutramine and its two metabolites in human plasma by LC–ESI-MS/MS and its application in a bioequivalence study

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Venkata Suresh Ponnuru

2012-08-01

Full Text Available Obesity can be considered as a chronic illness of epidemic proportion and its incidents have increased exponentially in recent years. The use of anti-obesity drugs such as sibutramine is somewhat helpful. There is a need to quantify such drugs in biological samples, which is generally quite difficult. In this report, we developed and validated a simple, sensitive and specific liquid chromatography–tandem mass spectrometry (LC–MS/MS method for the quantification of sibutramine (SB and its two metabolites N-des methyl sibutramine (DSB and N-di desmethyl sibutramine (DDSB in human plasma. Zorbax SB-C18 (4.6 mm×75 mm, 3.5 μm, 80 Å analytical column and 5 mM ammonium formate:acetonitrile (10:90, v/v mobile phase were used for chromatographic separation of SB, DSB and DDSB. Multiple reaction monitoring (MRM in the positive mode was used to detect SB, DSB and DDSB at m/z 280.3/124.9, 266.3/125.3 and 252.2/124.9, respectively. Liquid–liquid extraction was used for the extraction of analytes and internal standard from human plasma. This method was validated over a linear concentration range of 10.0–10,000.0 pg/mL for SB, DSB and DDSB with correlation coefficients (r of ≥0.9997. The drug and the two metabolites were stable in plasma samples. The validated method was successfully applied in a bioequivalence and pharmacokinetic study with human volunteers under fasting condition. Keywords: LC–ESI-MS/MS, Sibutramine, Human plasma, Bioequivalence, Pharmacokinetic study

Zinc Oxide Nanoparticles Influence Microflora in Ileal Digesta and Correlate Well with Blood Metabolites

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Yanni Feng

2017-06-01

Full Text Available Zinc oxide nanoparticles (ZnO NPs are used widely in consumer and industrial products, however, their influence on gut microbiota and metabolism and their mutual interactions are not fully understood. In this study, the effects of ZnO NPs on ileal bacterial communities, plasma metabolites, and correlations between them were investigated. Hens were fed with different concentrations of ZnO NPs [based on Zn; 0 mg/kg (control, 25 mg/kg, 50 mg/kg, and 100 mg/kg] for 9 weeks. Subsequently, ileal digesta and blood plasma were collected for analysis of microflora and metabolites, respectively. The V3-V4 region of the 16S rRNA gene of ileal digesta microbiota was sequenced using the Illumina HiSeq 2500 platform. The predominant bacterial community in the ileum belongs to the phylum Firmicutes. The richness of the bacterial community was negatively correlated with increasing amounts of ZnO NPs (r = -0.636, P < 0.01; when ZnO NP levels were at 100 mg/kg, microbiota diversity was significantly decreased (P < 0.05. The community structure determined by LEfSe analysis indicated that Bacilli, Fusobacteria, and Proteobacteria were changed, and Lactobacillus was reduced by ZnO NPs. Moreover, metabolism as analyzed by nuclear magnetic resonance (NMR indicated that glucose, some amino acids, and other metabolites were changed by ZnO NPs. Choline, lactate, and methionine were positively correlated with bacterial richness. In summary, ZnO NPs could influence the levels of microflora in ileal digesta, particularly Lactobacillus. Furthermore, the richness of the microbiota was related to changes in choline, lactate, and methionine metabolism.

PCBs and OH-PCBs in polar bear mother-cub pairs: a comparative study based on plasma levels in 1998 and 2008.

Science.gov (United States)

Bytingsvik, Jenny; Lie, Elisabeth; Aars, Jon; Derocher, Andrew E; Wiig, Øystein; Jenssen, Bjørn M

2012-02-15

The aim of this study was to examine the plasma concentrations and prevalence of polychlorinated biphenyls (PCBs) and hydroxylated PCB-metabolites (OH-PCBs) in polar bear (Ursus maritimus) mothers (n=26) and their 4 months old cubs-of-the-year (n=38) from Svalbard to gain insight into the mother-cub transfer, biotransformation and to evaluate the health risk associated with the exposure to these contaminants. As samplings were performed in 1997/1998 and 2008, we further investigated the differences in levels and pattern of PCBs between the two sampling years. The plasma concentrations of Σ(21)PCBs (1997/1998: 5710 ± 3090 ng/g lipid weight [lw], 2008: 2560 ± 1500 ng/g lw) and Σ(6)OH-PCBs (1997/1998: 228 ± 60 ng/g wet weight [ww], 2008: 80 ± 38 ng/g ww) in mothers were significantly lower in 2008 compared to in 1997/1998. In cubs, the plasma concentrations of Σ(21)PCBs (1997/1998: 14680 ± 5350 ng/g lw, 2008: 6070 ± 2590 ng/g lw) and Σ(6)OH-PCBs (1997/1998: 98 ± 23 ng/g ww, 2008: 49 ± 21 ng/g ww) were also significantly lower in 2008 than in 1997/1998. Σ(21)PCBs in cubs was 2.7 ± 0.7 times higher than in their mothers. This is due to a significant maternal transfer of these contaminants. In contrast, Σ(6)OH-PCBs in cubs were approximately 0.53 ± 0.16 times the concentration in their mothers. This indicates a lower maternal transfer of OH-PCBs compared to PCBs. The majority of the metabolite/precursor-ratios were lower in cubs compared to mothers. This may indicate that cubs have a lower endogenous capacity to biotransform PCBs to OH-PCBs than polar bear mothers. Exposure to PCBs and OH-PCBs is a potential health risk for polar bears, and the levels of PCBs and OH-PCBs in cubs from 2008 were still above levels associated with health effects in humans and wildlife. Copyright © 2012 Elsevier B.V. All rights reserved.

Concentrations in plasma clozapine levels in schizophrenic and schizoaffective patients.

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Iglesias García, Celso; Iglesias Alonso, Ana; Bobes, Julio

There is great variability in plasma levels of clozapine. The objective of this study is to know the characteristics of patients treated with clozapine and the relationship between them and the variability of plasma levels. Descriptive, cross-sectional study of all patients currently treated with clozapine in a Psychiatric Service with a diagnosis of schizophrenic psychosis or schizoaffective disorder. The present study assessed physical situation, psychopathology and functionality of the patients and explored the associations and correlations between clinical variables and plasma levels. We studied 39 patients, predominantly men, with negative and depressive symptoms and cardiovascular risk factors (metabolic syndrome and smoking). Significant variability in dose and even greater in clozapine levels were observed. The levels of clozapine at equal doses/kg of body weight were higher in non-smokers, they had positive correlation with BMI and negative correlation with systolic BP, disruptive behaviors and number of cigarettes consumed. Plasma level monitoring clozapine is an important tool to avoid clozapine plasma levels monitoring and minimize undesirable clinical situations (metabolic syndrome, sedation, negative symptoms and functional impairment). It is also important to control the effects of a smoking habit for optimum drug bioavailability. Copyright © 2017 SEP y SEPB. Publicado por Elsevier España, S.L.U. All rights reserved.

The plasma and cerebrospinal fluid pharmacokinetics of erlotinib and its active metabolite (OSI-420) after intravenous administration of erlotinib in non-human primates.

Science.gov (United States)

Meany, Holly J; Fox, Elizabeth; McCully, Cynthia; Tucker, Chris; Balis, Frank M

2008-08-01

Erlotinib hydrochloride is a small molecule inhibitor of epidermal growth factor receptor (EGFR). EGFR is over-expressed in primary brain tumors and solid tumors that metastasize to the central nervous system. We evaluated the plasma and cerebrospinal fluid (CSF) pharmacokinetics of erlotinib and its active metabolite OSI-420 after an intravenous (IV) dose in a non-human primate model. Erlotinib was administered as a 1 h IV infusion to four adult rhesus monkeys. Serial blood and CSF samples were drawn over 48 h and erlotinib and OSI-420 were quantified with an HPLC/tandem mass spectroscopic assay. Pharmacokinetic parameters were estimated using non-compartmental and compartmental methods. CSF penetration was calculated from the AUC(CSF):AUC(plasma). Erlotinib disappearance from plasma after a short IV infusion was biexponential with a mean terminal half-life of 5.2 h and a mean clearance of 128 ml/min per m(2). OSI-420 exposure (AUC) in plasma was 30% (range 12-59%) of erlotinib, and OSI-420 clearance was more than 5-fold higher than erlotinib. Erlotinib and OSI-420 were detectable in CSF. The CSF penetration (AUC(CSF):AUC(plasma)) of erlotinib and OSI-420 was OSI-420 are measurable in CSF after an IV dose. The drug exposure (AUC) in the CSF is limited relative to total plasma concentrations but is substantial relative the free drug exposure in plasma.

Enhanced nuclear level decay in hot dense plasmas

International Nuclear Information System (INIS)

Gosselin, G.; Morel, P.

2004-01-01

A model of nuclear level decay in a plasma environment is described. Nuclear excitation and decay by photon processes, nuclear excitation by electron capture, and decay by internal conversion are taken into account. The electrons in the plasma are described by a relativistic average atom model for the bound electrons and by a relativistic Thomas-Fermi-Dirac model for the free electrons. Nuclear decay of isomeric level may be enhanced through an intermediate level lying above the isomer. An enhanced nuclear decay rate may occur for temperatures far below the excitation energy of the transition to the intermediate level. In most cases, the enhancement factor may reach several decades

Prediction of Clinically Relevant Safety Signals of Nephrotoxicity through Plasma Metabolite Profiling

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W. B. Mattes

2013-01-01

Full Text Available Addressing safety concerns such as drug-induced kidney injury (DIKI early in the drug pharmaceutical development process ensures both patient safety and efficient clinical development. We describe a unique adjunct to standard safety assessment wherein the metabolite profile of treated animals is compared with the MetaMap Tox metabolomics database in order to predict the potential for a wide variety of adverse events, including DIKI. To examine this approach, a study of five compounds (phenytoin, cyclosporin A, doxorubicin, captopril, and lisinopril was initiated by the Technology Evaluation Consortium under the auspices of the Drug Safety Executive Council (DSEC. The metabolite profiles for rats treated with these compounds matched established reference patterns in the MetaMap Tox metabolomics database indicative of each compound’s well-described clinical toxicities. For example, the DIKI associated with cyclosporine A and doxorubicin was correctly predicted by metabolite profiling, while no evidence for DIKI was found for phenytoin, consistent with its clinical picture. In some cases the clinical toxicity (hepatotoxicity, not generally seen in animal studies, was detected with MetaMap Tox. Thus metabolite profiling coupled with the MetaMap Tox metabolomics database offers a unique and powerful approach for augmenting safety assessment and avoiding clinical adverse events such as DIKI.

Plasma total antioxidant capacity is associated with dietary intake and plasma level of antioxidants in postmenopausal women.

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Wang, Ying; Yang, Meng; Lee, Sang-Gil; Davis, Catherine G; Kenny, Anne; Koo, Sung I; Chun, Ock K

2012-12-01

Increased plasma total antioxidant capacity (TAC) has been associated with a high consumption of fruits and vegetables. However, limited information is available on whether plasma TAC reflects the dietary intake of antioxidants and the levels of individual antioxidants in plasma. By using three different assays, the study aimed to determine if plasma TAC can effectively predict dietary intake of antioxidants and plasma antioxidant status. Forty overweight and apparently healthy postmenopausal women were recruited. Seven-day food records and 12-h fasting blood samples were collected for dietary and plasma antioxidant assessments. Plasma TAC was determined by vitamin C equivalent antioxidant capacity (VCEAC), ferric-reducing ability of plasma (FRAP) and oxygen radical absorbance capacity (ORAC) assays. TAC values determined by VCEAC were highly correlated with FRAP (r=0.79, Pantioxidants and represents more closely the plasma antioxidant levels than ORAC and FRAP. Copyright © 2012 Elsevier Inc. All rights reserved.

The association between estimated average glucose levels and fasting plasma glucose levels

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Giray Bozkaya

2010-01-01

Full Text Available OBJECTIVE: The level of hemoglobin A1c (HbA1c, also known as glycated hemoglobin, determines how well a patient's blood glucose level has been controlled over the previous 8-12 weeks. HbA1c levels help patients and doctors understand whether a particular diabetes treatment is working and whether adjustments need to be made to the treatment. Because the HbA1c level is a marker of blood glucose for the previous 120 days, average blood glucose levels can be estimated using HbA1c levels. Our aim in the present study was to investigate the relationship between estimated average glucose levels, as calculated by HbA1c levels, and fasting plasma glucose levels. METHODS: The fasting plasma glucose levels of 3891 diabetic patient samples (1497 male, 2394 female were obtained from the laboratory information system used for HbA1c testing by the Department of Internal Medicine at the Izmir Bozyaka Training and Research Hospital in Turkey. These samples were selected from patient samples that had hemoglobin levels between 12 and 16 g/dL. The estimated glucose levels were calculated using the following formula: 28.7 x HbA1c - 46.7. Glucose and HbA1c levels were determined using hexokinase and high performance liquid chromatography (HPLC methods, respectively. RESULTS: A strong positive correlation between fasting plasma glucose levels and estimated average blood glucose levels (r=0.757, p<0.05 was observed. The difference was statistically significant. CONCLUSION: Reporting the estimated average glucose level together with the HbA1c level is believed to assist patients and doctors determine the effectiveness of blood glucose control measures.

Plasma oxalic acid and calcium levels in oxalate poisoning

Science.gov (United States)

Zarembski, P. M.; Hodgkinson, A.

1967-01-01

Observations are reported on five cases of suicide or attempted suicide by poisoning with oxalic acid or ethylene glycol. Elevated oxalic acid levels were observed in the plasma, stomach contents, and a number of tissues. Raised oxalic acid levels in plasma were associated with reduced total and ultrafilterable calcium levels. It is suggested that the reduction in plasma total calcium level is due mainly to the deposition of calcium oxalate in the soft tissues, but inhibition of the parathyroid glands may be a contributory factor. Microscopic examination of various tissues indicated that oxalic acid is deposited in the tissues in two forms: (1) crystalline calcium oxalate dihydrate in the kidney and (2) a non-crystalline complex of calcium oxalate and lipid in liver and other tissues. PMID:5602563

Mass spectrometry profiling reveals altered plasma levels of monohydroxy fatty acids and related lipids in healthy humans after controlled exposure to biodiesel exhaust.

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Gouveia-Figueira, Sandra; Karimpour, Masoumeh; Bosson, Jenny A; Blomberg, Anders; Unosson, Jon; Sehlstedt, Maria; Pourazar, Jamshid; Sandström, Thomas; Behndig, Annelie F; Nording, Malin L

2018-08-14

Experimental human exposure studies are an effective tool to study adverse health effects from acute inhalation of particulate matter and other constituents of air pollution. In this randomized and double-blinded crossover study, we investigated the systemic effect on bioactive lipid metabolite levels after controlled biodiesel exhaust exposure of healthy humans and compared it to filtered air at a separate exposure occasion. Eicosanoids and other oxylipins, as well as endocannabinoids and related lipids, were quantified in plasma from 14 healthy volunteers at baseline and at three subsequent time points (2, 6, and 24 h) after 1 h exposure sessions. Protocols based on liquid chromatography (LC) coupled to tandem mass spectrometry (MS/MS) methods were developed to detect temporal changes in circulating levels after biodiesel exhaust exposure. The exhaust was generated by a diesel engine fed with an undiluted rapeseed methyl ester fuel. Among the 51 analyzed lipid metabolites, PGF 2α , 9,10-DiHOME, 9-HODE, 5-HETE, 11-HETE, 12-HETE, and DEA displayed significant responsiveness to the biodiesel exhaust exposure as opposed to filtered air. Of these, 9-HODE and 5-HETE at 24 h survived the 10% false discovery rate cutoff (p emphasis on metabolites with inflammation related properties and implications on cardiovascular health and disease. These observations aid future investigations on air pollution effects, especially with regard to cardiovascular outcomes. Copyright © 2018 Elsevier B.V. All rights reserved.

Complicating factors in safety testing of drug metabolites: Kinetic differences between generated and preformed metabolites

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Prueksaritanont, Thomayant; Lin, Jiunn H.; Baillie, Thomas A.

2006-01-01

This paper aims to provide a scientifically based perspective on issues surrounding the proposed toxicology testing of synthetic drug metabolites as a means of ensuring adequate nonclinical safety evaluation of drug candidates that generate metabolites considered either to be unique to humans or are present at much higher levels in humans than in preclinical species. We put forward a number of theoretical considerations and present several specific examples where the kinetic behavior of a preformed metabolite given to animals or humans differs from that of the corresponding metabolite generated endogenously from its parent. The potential ramifications of this phenomenon are that the results of toxicity testing of the preformed metabolite may be misleading and fail to characterize the true toxicological contribution of the metabolite when formed from the parent. It is anticipated that such complications would be evident in situations where (a) differences exist in the accumulation of the preformed versus generated metabolites in specific tissues, and (b) the metabolite undergoes sequential metabolism to a downstream product that is toxic, leading to differences in tissue-specific toxicity. Owing to the complex nature of this subject, there is a need to treat drug metabolite issues in safety assessment on a case-by-case basis, in which a knowledge of metabolite kinetics is employed to validate experimental paradigms that entail administration of preformed metabolites to animal models

Physical activity opposes the age-related increase in skeletal muscle and plasma endothelin-1 levels and normalizes plasma endothelin-1 levels in individuals with essential hypertension.

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Nyberg, M; Mortensen, S P; Hellsten, Y

2013-03-01

Endothelin-1 has potent constrictor and proliferative activity in vascular smooth muscle, and essential hypertension and aging are associated with increased endothelin-1-mediated vasoconstrictor tone. The aim of this study was to investigate the effect of physical activity, hypertension and age on endothelin-1 levels in plasma and skeletal muscle and endothelin receptors in skeletal muscle in human subjects. In study 1, normotensive (46 ± 1 years, n = 11) and hypertensive (47 ± 1 years, n = 10) subjects were studied before and after 8 weeks of aerobic exercise training. In study 2, young (23 ± 1 years, n = 8), older lifelong sedentary (66 ± 2 years, n = 8) and older lifelong endurance-trained (62 ± 2 years, n = 8) subjects were studied in a cross-sectional design. Skeletal muscle and plasma endothelin-1 levels were increased with age and plasma endothelin-1 levels were higher in hypertensive than normotensive individuals. Eight weeks of exercise training normalized plasma endothelin-1 levels in the hypertensive subjects and increased the protein expression of the ET(A) receptor in skeletal muscle of normotensive subjects. Similarly, individuals that had performed lifelong physical activity had similar plasma and muscle endothelin-1 levels as the young controls and had higher ET(A) receptor levels. Our findings suggest that aerobic exercise training opposes the age-related increase in skeletal muscle and plasma endothelin-1 levels and normalizes plasma endothelin-1 levels in individuals with essential hypertension. This effect may explain some of the beneficial effects of training on the cardiovascular system in older and hypertensive subjects. © 2012 The Authors Acta Physiologica © 2012 Scandinavian Physiological Society.

Measurement of plasma neuropeptide Y levels with RIA in diabetic patients

International Nuclear Information System (INIS)

Cheng Guanghua; Zhang Xinlu; Yang Jun

2002-01-01

Objective: To investigate the clinical significance of the levels of plasma neuropeptide Y(NPY) in NIDDM patients with the occurrence of vascular complications. Methods: The plasma NPY levels were measured in 67 cases with DM (Group A: no Vascular complication, n = 38, Group B: with renal and retinal Vascular Changes, n = 29) and 37 normal subjects by radioimmunoassay. Results: NPY levels were higher in diabetic patients than those in normal subjects (p < 0.001). Also the plasma NPY levels were higher (p < 0.001) in diabetic patients with angiopathy (29 cases) than in those without it (38 cases). Conclusion: These data suggested that the changes of plasma NPY levels might be closely related to the occurrence and development of complications in DM patients

Stereoselective pharmacokinetics of moguisteine metabolites in healthy subjects.

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Bernareggi, A; Crema, A; Carlesi, R M; Castoldi, D; Ratti, E; Renoldi, M I; Ratti, D; Ceserani, R; Tognella, S

1995-01-01

We studied the pharmacokinetics of moguisteine, a racemic non-narcotic peripheral antitussive drug, in 12 healthy male subjects after a single oral administration of 200 mg. The unchanged drug was absent in plasma and urine of all subjects. Moguisteine was immediately and completely hydrolyzed to its main active metabolite, the free carboxylic acid M1. Therefore, we evaluated the kinetic profiles of M1, of its enantiomers R(+)-M1 and S(-)-M1, and of M1 sulfoxide optical isomers M2/I and M2/II by conventional and stereospecific HPLC. Maximum plasma concentrations for M1 (2.83 mg/l), M2/I (0.26 mg/l) and M2/II (0.40 mg/l), were respectively reached at 1.3, 1.6 and 1.5 h after moguisteine administration. Plasma concentrations declined after the peak with mean apparent terminal half-lives of 0.65 h (M1), 0.88 h (M2/I) and 0.84 h (M2/II). Most of the administered dose was recovered in urine within 6 h from moguisteine treatment. The systemic and renal clearance values indicated high renal extraction ratio for all moguisteine metabolites, and particularly for M1 sulfoxide optical isomers. Plasma concentration-time profiles and urinary excretion patterns for M1 enantiomers R(+)-M1 and S(-)-M1 were quite similar. Thus, for later moguisteine pharmacokinetic evaluations the investigation of the plasma concentration-time curve and the urinary excretion of the sole racemic M1 through non-stereospecific analytical methods may suffice in most cases.

Urinary composition and postprandial blood changes in H-secoisolariciresinol diglycoside (SDG) metabolites in rats do not differ between acute and chronic SDG treatments.

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Rickard, S E; Thompson, L U

2000-09-01

Although chronic exposure to secoisolariciresinol diglycoside (SDG) was shown to alter (3)H-SDG metabolite disposition in rats, the proportion of measured radioactivity attributed to known or unknown SDG metabolites was not determined. Using HPLC and GC-MS, two experiments were conducted to determine the effect of acute (1 d) vs. chronic (10 d) SDG treatment on major urinary metabolites of (3)H-SDG in female, Sprague-Dawley rats (70-72-d-old) over a 48-h period and if new urinary metabolites were detectable in rats fed nonradioactive flaxseed or SDG. A third experiment was conducted to determine changes in postprandial blood levels of (3)H-SDG metabolites over a 24-h period with acute or chronic SDG treatment. Regardless of treatment, enterodiol, enterolactone and secoisolariciresinol accounted for 75-80% of urine radioactivity. Four potential new lignan metabolites, two of which were detected in the urine of rats fed nonradioactive flaxseed or SDG, were found. Type of treatment had no effect on levels of individual urinary metabolites of (3)H-SDG. As observed for plasma lignans in women fed flaxseed, blood radioactivity peaked at 9 h and remained high until 24 h in both treatment groups, suggesting that blood lignan kinetics might be similar with flaxseed or SDG consumption and that they were comparable between humans and rats. In conclusion, the main urinary lignan metabolites were enterodiol, enterolactone and secoisolariciresinol. Urinary composition or blood levels of radioactive lignans were not affected by the duration of SDG exposure. Thus, while chronic SDG exposure alters lignan disposition in rats, it does not change the metabolite profile.

Plasma and Urinary Phenolic Profiles after Acute and Repetitive Intake of Wild Blueberry

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Rodrigo P. Feliciano

2016-08-01

Full Text Available Recent studies have shown that blueberries may have cardiovascular and cognitive health benefits. In this work, we investigated the profile of plasma and urine (polyphenol metabolites after acute and daily consumption of wild blueberries for 30 days in 18 healthy men. The inter-individual variability in plasma and urinary polyphenol levels was also investigated. Blood samples were collected at baseline and 2 h post-consumption on day 1 and day 30. Twenty-four-hour urine was also collected on both days. A total of 61 phenolic metabolites were quantified in plasma at baseline, of which 43 increased after acute or chronic consumption of blueberries over one month. Benzoic and catechol derivatives represented more than 80% of the changes in phenolic profile after 2 h consumption on day 1, whereas hippuric and benzoic derivatives were the major compounds that increased at 0 and 2 h on day 30, respectively. The total (polyphenol urinary excretion remained unchanged after 30 days of wild blueberry intake. The inter-individual variability ranged between 40%–48% in plasma and 47%–54% in urine. Taken together, our results illustrate that blueberry (polyphenols are absorbed and extensively metabolized by phase II enzymes and by the gut microbiota, leading to a whole array of metabolites that may be responsible for the beneficial effects observed after blueberry consumption.

Plasma and Urinary Phenolic Profiles after Acute and Repetitive Intake of Wild Blueberry.

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Feliciano, Rodrigo P; Istas, Geoffrey; Heiss, Christian; Rodriguez-Mateos, Ana

2016-08-25

Recent studies have shown that blueberries may have cardiovascular and cognitive health benefits. In this work, we investigated the profile of plasma and urine (poly)phenol metabolites after acute and daily consumption of wild blueberries for 30 days in 18 healthy men. The inter-individual variability in plasma and urinary polyphenol levels was also investigated. Blood samples were collected at baseline and 2 h post-consumption on day 1 and day 30. Twenty-four-hour urine was also collected on both days. A total of 61 phenolic metabolites were quantified in plasma at baseline, of which 43 increased after acute or chronic consumption of blueberries over one month. Benzoic and catechol derivatives represented more than 80% of the changes in phenolic profile after 2 h consumption on day 1, whereas hippuric and benzoic derivatives were the major compounds that increased at 0 and 2 h on day 30, respectively. The total (poly)phenol urinary excretion remained unchanged after 30 days of wild blueberry intake. The inter-individual variability ranged between 40%-48% in plasma and 47%-54% in urine. Taken together, our results illustrate that blueberry (poly)phenols are absorbed and extensively metabolized by phase II enzymes and by the gut microbiota, leading to a whole array of metabolites that may be responsible for the beneficial effects observed after blueberry consumption.

Fully Automated Trimethylsilyl (TMS Derivatisation Protocol for Metabolite Profiling by GC-MS

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Erica Zarate

2016-12-01

Full Text Available Gas Chromatography-Mass Spectrometry (GC-MS has long been used for metabolite profiling of a wide range of biological samples. Many derivatisation protocols are already available and among these, trimethylsilyl (TMS derivatisation is one of the most widely used in metabolomics. However, most TMS methods rely on off-line derivatisation prior to GC-MS analysis. In the case of manual off-line TMS derivatisation, the derivative created is unstable, so reduction in recoveries occurs over time. Thus, derivatisation is carried out in small batches. Here, we present a fully automated TMS derivatisation protocol using robotic autosamplers and we also evaluate a commercial software, Maestro available from Gerstel GmbH. Because of automation, there was no waiting time of derivatised samples on the autosamplers, thus reducing degradation of unstable metabolites. Moreover, this method allowed us to overlap samples and improved throughputs. We compared data obtained from both manual and automated TMS methods performed on three different matrices, including standard mix, wine, and plasma samples. The automated TMS method showed better reproducibility and higher peak intensity for most of the identified metabolites than the manual derivatisation method. We also validated the automated method using 114 quality control plasma samples. Additionally, we showed that this online method was highly reproducible for most of the metabolites detected and identified (RSD < 20 and specifically achieved excellent results for sugars, sugar alcohols, and some organic acids. To the very best of our knowledge, this is the first time that the automated TMS method has been applied to analyse a large number of complex plasma samples. Furthermore, we found that this method was highly applicable for routine metabolite profiling (both targeted and untargeted in any metabolomics laboratory.

Rapid sensitive validated UPLC–MS method for determination of venlafaxine and its metabolite in rat plasma: Application to pharmacokinetic study

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Sunil Kumar Dubey

2013-12-01

Full Text Available A new ultra-performance liquid chromatography–electrospray ionization mass spectrometry (UPLC–MS/ESI method for simultaneous determination of venlafaxine (VEN and its metabolite O-desmethylvenlafaxine (ODV in rat plasma has been developed and validated using Venlafaxine d6 as the internal standard. The compounds and internal standard were extracted from plasma by solid phase extraction. The UPLC separation of the analytes was performed on ACQUITY UPLC® BEH Shield RP18 (1.7 µm, 100 mm×2.1 mm column, using isocratic elution with mobile phase constituted of water (containing 2 mM ammonium acetate: acetonitrile (20:80, v/v at a flow rate of 0.3 mL/min. All of the analytes were eluted within 1.5 min. The compounds were ionized in the electrospray ionization (ESI ion source of the mass spectrometer, operating in multiple reaction monitoring (MRM and positive ion mode. The precursor to product ion transitions monitored for VEN, ODV and Venlafaxine d6 were m/z 278.3→121.08, 264.2→107.1 and 284.4→121.0, respectively. The developed and validated method was used for the pharmacokinetic study of VEN in rats. Keywords: Venlafaxine, O-desmethylvenlafaxine, Metabolite, UPLC–MS/ES

Concentrations of isoflavones and their metabolites in the blood of pregnant and non-pregnant heifers fed soy bean.

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Woclawek-Potocka, Izabela; Piskula, Mariusz Krzysztof; Bah, Mamadou; Siemieniuch, Marta Jolanta; Korzekwa, Anna; Brzezicka, Edyta; Skarzynski, Dariusz Jan

2008-10-01

The present study compared the changes in isoflavones (daidzein and genistein) and their metabolite (equol and para-ethyl-phenol) concentrations in the blood plasma of cyclic and pregnant heifers after feeding with soy bean. Twelve healthy heifers were divided into three groups: cyclic heifers (days 8-12 of the estrous cycle; control group; n=4), an early pregnancy group (2 months pregnant; n=4) and a late pregnancy group (8 months pregnant; n=4). All heifers were fed a single dose of 2.5 kg of soy bean and then blood samples were taken from the jugular vein for 8 h at predetermined intervals. The concentrations of soy bean-derived isoflavones and their active metabolites were measured in the blood plasma on an HPLC system. In the blood plasma of the early- and late-pregnant heifers, we found lower concentrations and time-dependent decreases in daidzein and genistein in comparison to cyclic heifers (P0.05). In conclusion, physiological status (cyclicity or pregnancy) of the females influenced the concentrations of isoflavone metabolites in the blood plasma of the heifers. The stage of pregnancy affects isoflavone absorption, biotransformation and metabolism differently and results in higher concentrations of active metabolites of isoflavones during early pregnancy in comparison to their lower concentrations during late pregnancy. Therefore, we surmise that cows are more sensitive to active isoflavone metabolite actions during early pregnancy than cyclic heifers and heifers in late pregnancy.

Depletion by styrene of glutathione in plasma and bronchioalveolar lavage fluid of non-Swiss albino (NSA) mice.

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Carlson, Gary P

2010-01-01

Styrene is a widely used chemical, but it is known to produce lung and liver damage in mice. This may be related to oxidative stress associated with the decrease in the levels of reduced glutathione (GSH) in the target tissues. The purpose of this study was to investigate the effect of styrene and its primary metabolites R-styrene oxide (R-SO) and S-styrene oxide (S-SO) on GSH levels in the lung lumen, as determined by amounts of GSH in bronchioalveolar lavage fluid (BALF) and in plasma. When non-Swiss albino (NSA) mice were administered styrene (600 mg/kg, ip), there was a significant fall in GSH levels in both BALF and plasma within 3 h. These returned to control levels by 12 h. The active metabolite R-SO (300 mg/kg, ip) also produced significant decreases in GSH in both BALF and plasma, but S-SO was without marked effect. Since GSH is a principal antioxidant in the lung epithelial lining fluid, this fall due to styrene may exert a significant influence on the ability of the lung to buffer oxidative damage.

Profiling adrenal 11β-hydroxyandrostenedione metabolites in prostate cancer cells, tissue and plasma: UPC2-MS/MS quantification of 11β-hydroxytestosterone, 11keto-testosterone and 11keto-dihydrotestosterone.

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du Toit, Therina; Bloem, Liezl M; Quanson, Jonathan L; Ehlers, Riaan; Serafin, Antonio M; Swart, Amanda C

2017-02-01

Adrenal C 19 steroids serve as precursors to active androgens in the prostate. Androstenedione (A4), 11β-hydroxyandrostenedione (11OHA4) and 11β-hydroxytestosterone (11OHT) are metabolised to potent androgen receptor (AR) agonists, dihydrotestosterone (DHT), 11-ketotestosterone (11KT) and 11-ketodihydrotestosterone (11KDHT). The identification of 11OHA4 metabolites, 11KT and 11KDHT, as active androgens has placed a new perspective on adrenal C11-oxy C 19 steroids and their contribution to prostate cancer (PCa). We investigated adrenal androgen metabolism in normal epithelial prostate (PNT2) cells and in androgen-dependent prostate cancer (LNCaP) cells. We also analysed steroid profiles in PCa tissue and plasma, determining the presence of the C 19 steroids and their derivatives using ultra-performance liquid chromatography (UHPLC)- and ultra-performance convergence chromatography tandem mass spectrometry (UPC 2 -MS/MS). In PNT2 cells, sixty percent A4 (60%) was primarily metabolised to 5α-androstanedione (5αDIONE) (40%), testosterone (T) (10%), and androsterone (AST) (10%). T (30%) was primarily metabolised to DHT (10%) while low levels of A4, 5αDIONE and 3αADIOL (≈20%) were detected. Conjugated steroids were not detected and downstream products were present at <0.05μM. Only 20% of 11OHA4 and 11OHT were metabolised with the former yielding 11keto-androstenedione (11KA4), 11KDHT and 11β-hydroxy-5α-androstanedione (11OH-5αDIONE) and the latter yielding 11OHA4, 11KT and 11KDHT with downstream products <0.03μM. In LNCaP cells, A4 (90%) was metabolised to AST-glucuronide via the alternative pathway while T was detected as T-glucuronide with negligible conversion to downstream products. 11OHA4 (80%) and 11OHT (60%) were predominantly metabolised to 11KA4 and 11KT and in both assays more than 50% of 11KT was detected in the unconjugated form. In tissue, we detected C11-oxy C 19 metabolites at significantly higher levels than the C 19 steroids, with

Influence of the collection tube on metabolomic changes in serum and plasma.

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López-Bascón, M A; Priego-Capote, F; Peralbo-Molina, A; Calderón-Santiago, M; Luque de Castro, M D

2016-04-01

Major threats in metabolomics clinical research are biases in sampling and preparation of biological samples. Bias in sample collection is a frequently forgotten aspect responsible for uncontrolled errors in metabolomics analysis. There is a great diversity of blood collection tubes for sampling serum or plasma, which are widely used in metabolomics analysis. Most of the existing studies dealing with the influence of blood collection on metabolomics analysis have been restricted to comparison between plasma and serum. However, polymeric gel tubes, which are frequently proposed to accelerate the separation of serum and plasma, have not been studied. In the present research, samples of serum or plasma collected in polymeric gel tubes were compared with those taken in conventional tubes from a metabolomics perspective using an untargeted GC-TOF/MS approach. The main differences between serum and plasma collected in conventional tubes affected to critical pathways such as the citric acid cycle, metabolism of amino acids, fructose and mannose metabolism and that of glycerolipids, and pentose and glucuronate interconversion. On the other hand, the polymeric gel only promoted differences at the metabolite level in serum since no critical differences were observed between plasma collected with EDTA tubes and polymeric gel tubes. Thus, the main changes were attributable to serum collected in gel and affected to the metabolism of amino acids such as alanine, proline and threonine, the glycerolipids metabolism, and two primary metabolites such as aconitic acid and lactic acid. Therefore, these metabolite changes should be taken into account in planning an experimental protocol for metabolomics analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

Plasma taurine levels are not affected by vigabatrin in pediatric patients.

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Spelbrink, Emily M; Mabud, Tarub S; Reimer, Richard; Porter, Brenda E

2016-08-01

Vigabatrin is a highly effective antiseizure medication, but its use is limited due to concerns about retinal toxicity. One proposed mechanism for this toxicity is vigabatrin-mediated reduction of taurine. Herein we assess plasma taurine levels in a retrospective cohort of children with epilepsy, including a subset receiving vigabatrin. All children who underwent a plasma amino acid analysis as part of their clinical evaluation between 2006 and 2015 at Stanford Children's Health were included in the analysis. There were no significant differences in plasma taurine levels between children taking vigabatrin (n = 16), children taking other anti-seizure medications, and children not taking any anti-seizure medication (n = 556) (analysis of variance [ANOVA] p = 0.841). There were, however, age-dependent decreases in plasma taurine levels. Multiple linear regression revealed no significant association between vigabatrin use and plasma taurine level (p = 0.87) when controlling for age. These results suggest that children taking vigabatrin maintain normal plasma taurine levels, although they leave unanswered whether taurine supplementation is necessary or sufficient to prevent vigabatrin-associated visual field loss. They also indicate that age should be taken into consideration when evaluating taurine levels in young children. Wiley Periodicals, Inc. © 2016 International League Against Epilepsy.

Application of dried blood spot cards to determine olive oil phenols (hydroxytyrosol metabolites) in human blood.

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de Las Hazas, María Carmen López; Motilva, Maria José; Piñol, Carme; Macià, Alba

2016-10-01

In this study, a fast and simple blood sampling and sample pre-treatment method based on the use of the dried blood spot (DBS) cards and ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) for the quantification of olive oil phenolic metabolites in human blood was developed and validated. After validation, the method was applied to determine hydroxytyrosol metabolites in human blood samples after the acute intake of an olive oil phenolic extract. Using the FTA DMPK-A DBS card under optimum conditions, with 20µL as the blood solution volume, 100µL of methanol/Milli-Q water (50/50, v/v) as the extraction solvent and 7 disks punched out from the card, the main hydroxytyrosol metabolites (hydroxytyrosol-3-O-sulphate and hydroxytyrosol acetate sulphate) were identified and quantified. The developed methodology allowed detecting and quantifying the generated metabolites at low μM levels. The proposed method is a significant improvement over existing methods to determine phenolic metabolites circulating in blood and plasma samples, thus making blood sampling possible with the volunteer pricking their own finger, and the subsequent storage of the blood in the DBS cards prior to chromatographic analysis. Copyright © 2016 Elsevier B.V. All rights reserved.

Relationship between respiratory failure and plasma noradrenaline levels in amyotrophic lateral sclerosis.

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Yamashita, A; Koike, Y; Takahashi, A; Hirayama, M; Murakami, N; Sobue, G

1997-08-01

We evaluated plasma noradrenaline (NA) levels at test and during head-up tilt test in 20 patients with sporadic amyotrophic lateral sclerosis (ALS). Their fasting plasma NA levels ranged from 195 to 4227 pg/ml. The average plasma NA level was 483 pg/ml in five ambulatory patients, 341 in two wheelchair-bound patients, 1264 in 11 bedridden patients, and 208 in two respirator-dependent patients whose disability grading was the worst among the four groups. Arterial carbon dioxide (PCO2) was evaluated as a measure of respiratory function. The coefficient of correlation between PCO2 and plasma NA was r = 0.654 (p respiratory failure or lower motor neuron dysfunction may relate to the elevation of plasma NA levels. In the two bedridden patients, plasma NA levels and heart rate at rest increased significantly as the disease progressed. Cardiovascular responses to head-up tilting were normal. These data suggest that the elevation of plasma NA levels may be related to progression of respiratory failure and lower motor neuron dysfunction. In conclusion, sympathetic hyperactivity in ALS is considered to be not primary, but secondary to somatic motor disabilities and respiratory failure.

Primary, Secondary Metabolites, H2O2, Malondialdehyde and Photosynthetic Responses of Orthosiphon stimaneus Benth. to Different Irradiance Levels

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Mohd Hafiz Ibrahim

2012-01-01

Full Text Available The resource availability hypothesis predicts an increase in the allocation to secondary metabolites when carbon gain is improved relative to nutrient availability, which normally occurs during periods of low irradiance. The present work was carried out to confirm this hypothesis by investigating the effects of decreasing irradiance on the production of plant secondary metabolites (flavonoids and phenolics in the herbal plant Orthosiphon stamineus, and to characterize this production by carbohydrate, H2O2, and malondialdehyde (MDA levels, net photosynthesis, leaf chlorophyll content and carbon to nitrogen ratio (C/N. Four levels of irradiance (225, 500, 625 and 900 µmol/m2/s were imposed onto two-week old seedlings for 12 weeks in a randomized complete block design experiment. Peak production of total flavonoids, phenolics, soluble sugar, starch and total non-structural carbohydrate ocurred under low irradiance of 225 µmol/m2/s, and decreased with increasing irradiance. The up-regulation of secondary metabolites could be explained by the concomitant increases in H2O2 and MDA activities under low irradiance. This condition also resulted in enhanced C/N ratio signifying a reduction in nitrogen levels, which had established significant negative correlations with net photosynthesis, total biomass and total chlorophyll content, indicating the possible existence of a trade-off between growth and secondary metabolism under low irradiance with reduced nitrogen content. The competition between total chlorophyll and secondary metabolites production, as exhibited by the negative correlation coefficient under low irradiance, also suggests a sign of gradual switch of investment from chlorophyll to polyphenols production.

Study of plasma adrenomedullin level in normal pregnancy and preclampsia.

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Senna, Azza Abo; Zedan, Magda; el-Salam, Gamal E Abd; el-Mashad, Ashraf I

2008-02-06

The aim of this study was to evaluate whether maternal circulating adrenomedullin (AM) values in patients with preeclampsia are different from those in normotensive pregnant women at different gestational ages. In a prospective clinical study, 90 women aged 17 to 40 years old, were divided into 4 main groups: group I (45 women): Normotensive pregnant women at first trimester (15 women), second trimester (15 women), and third trimester (15 women) of pregnancies. Group II (15 women): Pregnant women with preeclampsia at 25 to 38 weeks of gestation. Group III (15 women): Normotensive healthy nonpregnant women. Group IV (15 women): Hypertensive nonpregnant women. The plasma AM concentration was measured in all women by using enzyme immunoassay kits. Plasma AM levels in pregnant women with normal blood pressure at different gestational ages (first, second, and third trimesters) were statistically significantly higher than those detected in nonpregnant normotensive women and significantly increased with increasing gestational age (P < .001). Moreover, there was significant positive correlation between plasma AM levels and increasing gestational age (r = 0.915, P < .001). Preeclamptic patients had the highest mean plasma AM levels compared with all other groups, which is statistically significant (P < .001) and there was a significant positive correlation between plasma AM levels and systolic blood pressure, diastolic blood pressure, severity of preeclampsia, and proteinuria in pregnant patients with preeclampsia. Maternal plasma AM concentration increases throughout pregnancy and increases as gestational age progresses. AM production starts very early in gestation, suggesting that it may have an important role in human reproduction, from implantation to delivery. Maternal plasma AM level in preeclampsia appears to be higher than that in normal pregnancy.

Progranulin Levels in Plasma and Cerebrospinal Fluid in Granulin Mutation Carriers

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Lieke H.H. Meeter

2016-07-01

Full Text Available Background: Pathogenic mutations in the granulin gene (GRN are causative in 5-10% of patients with frontotemporal dementia (FTD, mostly leading to reduced progranulin protein (PGRN levels. Upcoming therapeutic trials focus on enhancing PGRN levels. Methods: Fluctuations in plasma PGRN (n = 41 and its relationship with cerebrospinal fluid (CSF, n = 32 and specific single nucleotide polymorphisms were investigated in pre- and symptomatic GRN mutation carriers and controls. Results: Plasma PGRN levels were lower in carriers than in controls and showed a mean coefficient of variation of 5.3% in carriers over 1 week. Although plasma PGRN correlated with CSF PGRN in carriers (r = 0.54, p = 0.02, plasma only explained 29% of the variability in CSF PGRN. rs5848, rs646776 and rs1990622 genotypes only partly explained the variability of PGRN levels between subjects. Conclusions: Plasma PGRN is relatively stable over 1 week and therefore seems suitable for treatment monitoring of PGRN-enhancing agents. Since plasma PGRN only moderately correlated with CSF PGRN, CSF sampling will additionally be needed in therapeutic trials.

Significance of metabolites in bioequivalence: losartan potassium as a case study.

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Charoo, Naseem Ahmad; Cristofoletti, Rodrigo; Khatri, Aamer Roshanali; Ali, Areeg Anwer

2014-06-01

Estimation of metabolite data as a supportive evidence of comparable therapeutic outcome is recommended by various guidance documents. However, a consensus on using it solely to establish bioequivalence (BE) is lacking as parent drug is believed to detect pharmacokinetic differences between test and reference formulations better. Four BE studies of losartan potassium reported in the literature are reviewed. In all the four studies, 90% confidence intervals (CIs) of geometric mean ratios of the test and reference formulations for maximum blood drug concentration (Cmax ) of losartan potassium were outside the acceptable range of 80%-125%, whereas, 90% CIs for its active metabolite, losartan carboxylic acid (LCA), were within the acceptance criteria. Although BE with respect to area under the plasma concentration versus time profile curve was demonstrated in all the cases, BE with respect to Cmax could not be established. However, marketing authorization in all the four cases was granted based on scientific evidence that LCA is 10-40 times more potent than losartan, LCA exhibited higher plasma concentration levels than losartan, pharmacodynamic effects correlate with LCA, and losartan shows wide therapeutic index. Further, widened CI limits for losartan were accepted. Losartan presents an opportunity in the diligence of the principles of quality risk management for selecting moiety on which BE decision must be based. © 2014 Wiley Periodicals, Inc. and the American Pharmacists Association.

Liquid-chromatography mass spectrometry (LC-MS) of steroid hormone metabolites and its applications

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Penning, Trevor M.; Lee, Seon-Hwa; Jin, Yi; Gutierrez, Alejandro; Blair, Ian A.

2010-01-01

Advances in liquid chromatography-mass spectrometry (LC-MS) can be used to measure steroid hormone metabolites in vitro and in vivo. We find that LC-Electrospray Ionization (ESI)-MS using a LCQ ion trap mass spectrometer in the negative ion mode can be used to monitor the product profile that results from 5α–dihydrotestosterone(DHT)-17β-glucuronide, DHT-17β-sulfate, and tibolone-17β-sulfate reduction catalyzed by human members of the aldo-keto reductase (AKR) 1C subfamily and assign kinetic constants to these reactions. We also developed a stable-isotope dilution LC-electron capture atmospheric pressure chemical ionization (ECAPCI)-MS method for the quantitative analysis of estrone (E1) and its metabolites as pentafluorobenzyl (PFB) derivatives in human plasma in the attomole range. The limit of detection for E1-PFB was 740 attomole on column. Separations can be performed using normal-phase LC because ionization takes place in the gas phase rather than in solution. This permits efficient separation of the regioisomeric 2- and 4-methoxy-E1. The method was validated for the simultaneous analysis of plasma E2 and its metabolites: 2-methoxy-E2, 4-methoxy-E2, 16α-hydroxy-E2, estrone (E1), 2-methoxy-E1, 4-methoxy-EI, and 16α-hydroxy-E1 from 5 pg/mL to 2,000 pg/mL. Our LC-MS methods have sufficient sensitivity to detect steroid hormone levels in prostate and breast tumors and should aid their molecular diagnosis and treatment. PMID:20083198

Decline of plasma 5alpha-dihydrotestosterone (DHT) levels upon testosterone administration to elderly men with subnormal plasma testosterone and high DHT levels.

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Gooren, L J; Saad, F; Haide, A; Yassin, A

2008-10-01

The study was performed to measure the impact of testosterone (T) administration on circulating levels of 5alpha-dihydrotestosterone (DHT). Group 1 (32 men; mean age 61 years; mean T 6.9 +/- 1.9 nmol l(-1)) were treated for 15 months with long-acting T undecanoate. Group 2 (23 men, mean age 60 years, mean T 7.6 +/- 2.0 nmol l(-1)) were treated for 9 months with T gel. Plasma T and DHT were measured before and after 9 months T administration. In the men treated with T undecanoate plasma T and DHT were also measured after 12 and 15 months. Before T administration, plasma DHT ranged from 0.39 to 1.76 nmol l(-1) (0.30-1.90 nmol l(-1)). Mean DHT declined upon T administration from 0.95 +/- 0.50 to 0.55 +/- 0.30 nmol l(-1) (P DHT > 0.60 nmol l(-1) had fallen from 1.29 +/- 0.50 to 0.70 +/- 0.60 nmol l(-1) (P DHT levels declined upon T administration when they were in the higher range of normal (>0.6 nmol l(-1)), with a profound shift of DHT/T ratios presumed to be an indicator of a reduced 5alpha-reductase activity. Below plasma DHT levels of 0.6 nmol l(-1), responses of plasma DHT to T administration varied.

Effect of carvedilol treatment on plasma neuropeptides levels in patients with essential hypertension

International Nuclear Information System (INIS)

Li Qian; Cheng Guanghua; Yang Jian

2008-01-01

Objective: To study the changes of plasma neuropeptide Y(NPY) and neurotension (NT) levels in patients with essential hypertension after treatment with carvedilol. Methods: Blood pressure and plasma NPY and NT concentrations (with RIA) were measured in 56 patients with essential hypertension both before and after carvedilol therapy (5-10 mg bid) for 3 months as well as 30 controls. Results: Before treatment plasma NPY levels were significantly higher in hypertensive patients than those in controls (P<0.01), but plasma NT levels were significantly lower (P also <0.01). After carvedilol treatment, blood pressure and plasma NPY levels were reduced significantly and plasma NT levels were increased significantly. Conclusion: Treatment with carvedilol results in the correction of plasma concentrations of NPY and NT in patients with essential hypertension, the effect may be related to blood pressure decrease. (authors)

High salt intake increases plasma trimethylamine N-oxide (TMAO) concentration and produces gut dysbiosis in rats.

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Bielinska, Klaudia; Radkowski, Marek; Grochowska, Marta; Perlejewski, Karol; Huc, Tomasz; Jaworska, Kinga; Motooka, Daisuke; Nakamura, Shota; Ufnal, Marcin

2018-03-22

A high-salt diet is considered a cardiovascular risk factor; however, the mechanisms are not clear. Research suggests that gut bacteria-derived metabolites such as trimethylamine N-oxide (TMAO) are markers of cardiovascular diseases. We evaluated the effect of high salt intake on gut bacteria and their metabolites plasma level. Sprague Dawley rats ages 12-14 wk were maintained on either water (controls) or 0.9% or 2% sodium chloride (NaCl) water solution (isotonic and hypertonic groups, respectively) for 2 wk. Blood plasma, urine, and stool samples were analyzed for concentrations of trimethylamine (TMA; a TMAO precursor), TMAO, and indoxyl sulfate (indole metabolite). The gut-blood barrier permeability to TMA and TMA liver clearance were assessed at baseline and after TMA intracolonic challenge test. Gut bacterial flora was analyzed with a 16S ribosomal ribonucleic acid (rRNA) gene sequence analysis. The isotonic and hypertonic groups showed a significantly higher plasma TMAO and significantly lower 24-hr TMAO urine excretion than the controls. However, the TMA stool level was similar between the groups. There was no significant difference between the groups in gut-blood barrier permeability and TMA liver clearance. Plasma indoxyl concentration and 24-hr urine indoxyl excretion were similar between the groups. There was a significant difference between the groups in gut bacteria composition. High salt intake increases plasma TMAO concentration, which is associated with decreased TMAO urine excretion. Furthermore, high salt intake alters gut bacteria composition. These findings suggest that salt intake affects an interplay between gut bacteria and their host homeostasis. Copyright © 2018 Elsevier Inc. All rights reserved.

Data Normalization of (1)H NMR Metabolite Fingerprinting Data Sets in the Presence of Unbalanced Metabolite Regulation.

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Hochrein, Jochen; Zacharias, Helena U; Taruttis, Franziska; Samol, Claudia; Engelmann, Julia C; Spang, Rainer; Oefner, Peter J; Gronwald, Wolfram

2015-08-07

Data normalization is an essential step in NMR-based metabolomics. Conducted properly, it improves data quality and removes unwanted biases. The choice of the appropriate normalization method is critical and depends on the inherent properties of the data set in question. In particular, the presence of unbalanced metabolic regulation, where the different specimens and cohorts under investigation do not contain approximately equal shares of up- and down-regulated features, may strongly influence data normalization. Here, we demonstrate the suitability of the Shapiro-Wilk test to detect such unbalanced regulation. Next, employing a Latin-square design consisting of eight metabolites spiked into a urine specimen at eight different known concentrations, we show that commonly used normalization and scaling methods fail to retrieve true metabolite concentrations in the presence of increasing amounts of glucose added to simulate unbalanced regulation. However, by learning the normalization parameters on a subset of nonregulated features only, Linear Baseline Normalization, Probabilistic Quotient Normalization, and Variance Stabilization Normalization were found to account well for different dilutions of the samples without distorting the true spike-in levels even in the presence of marked unbalanced metabolic regulation. Finally, the methods described were applied successfully to a real world example of unbalanced regulation, namely, a set of plasma specimens collected from patients with and without acute kidney injury after cardiac surgery with cardiopulmonary bypass use.

Quantification of vorinostat and its main metabolites in plasma and intracellular vorinostat in PBMCs by liquid chromatography coupled to tandem mass spectrometry and its relation to histone deacetylase activity in human blood.

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Liu, Lu; Detering, Jan-Christoph; Milde, Till; Haefeli, Walter Emil; Witt, Olaf; Burhenne, Jürgen

2014-08-01

Vorinostat (suberoylanilide hydroxamic acid) is the first approved histone deacetylase (HDAC) inhibitor for the treatment of cutaneous T-cell lymphoma after progressive disease following two systemic therapies. Intracellular access of vorinostat is essential to exert its epigenetic effects. Therefore, we studied the relationship between vorinostat extracellular (plasma) and intracellular (peripheral blood mononuclear cells, PBMCs) concentration and assessed its concentration-effect relationship by HDAC activity testing. Assays were developed and validated for the low nanomolar quantification of vorinostat and two inactive metabolites in human plasma and PBMCs. For the vorinostat extraction from plasma and PBMCs solid-phase extraction and liquid-liquid extraction methods were applied. Extraction recoveries ranged from 88.6% to 114.4% for all analytes and extraction methods. Extracts were chromatographed on a Phenomenex Luna column isocratically (plasma) or by gradient (PBMCs) consisting of acidic ammonium acetate, acetonitrile, and methanol. The analytes were quantified using deuterated internal standards and positive electrospray tandem mass spectrometry (multiple reaction monitoring) with lower limits of quantification of 11.0 ng/mL (plasma) and 0.1 ng/3 × 10(6) cells (PBMCs). The calibrated ranges were linear for vorinostat in plasma 11.0-1100 (11,000) ng/mL (metabolites) and PBMCs 0.1-10.0 ng/3 × 10(6) cells with correlation coefficients >0.99, an overall accuracy varying between -6.7% and +3.8% in plasma, -8.1% and -1.5% in PBMCs, and an overall precision ranging from 3.2% to 6.1% in plasma and 0.8% to 4.0% in PBMCs (SD batch-to-batch). The application to blood samples from healthy volunteers incubated with vorinostat revealed accumulation of vorinostat in PBMCs, effective intracellular HDAC inhibition at therapeutic vorinostat concentrations and a direct vorinostat concentration dependency to HDAC inhibition. Copyright © 2014 Elsevier B.V. All rights

Developmental social isolation affects adult behavior, social interaction, and dopamine metabolite levels in zebrafish.

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Shams, Soaleha; Amlani, Shahid; Buske, Christine; Chatterjee, Diptendu; Gerlai, Robert

2018-01-01

The zebrafish is a social vertebrate and an excellent translational model for a variety of human disorders. Abnormal social behavior is a hallmark of several human brain disorders. Social behavioral problems can arise as a result of adverse early social environment. Little is known about the effects of early social isolation in adult zebrafish. We compared zebrafish that were isolated for either short (7 days) or long duration (180 days) to socially housed zebrafish, testing their behavior across ontogenesis (ages 10, 30, 60, 90, 120, 180 days), and shoal cohesion and whole-brain monoamines and their metabolites in adulthood. Long social isolation increased locomotion and decreased shoal cohesion and anxiety in the open-field in adult. Additionally, both short and long social isolation reduced dopamine metabolite levels in response to social stimuli. Thus, early social isolation has lasting effects in zebrafish, and may be employed to generate zebrafish models of human neuropsychiatric conditions. © 2017 Wiley Periodicals, Inc.

Changes in plasma TIMP-1 levels after resection for primary colorectal cancer

DEFF Research Database (Denmark)

Frederiksen, C.; Lomholt, A.F.; Davis, G.J.

2009-01-01

BACKGROUND: Increased plasma levels of tissue inhibitor of metalloproteinases (TIMP-1) are associated with poor outcome in colorectal cancer (CRC), however postoperative changes in plasma TIMP-1 levels after resections for CRC have not been thoroughly evaluated. MATERIALS AND METHODS: Plasma samp...

Simultaneous quantification of MTC-220 and its metabolites in beagle dog plasma by liquid chromatography-tandem mass spectrometry.

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Liu, Xin; Zhao, Manman; Mi, Jiaqi; Liu, Zhihao; Hu, Jinping; Sheng, Li; Wang, Baolian; Li, Dan; Yang, Shuang; Li, Yan

2014-10-01

A sensitive LC-ESI-MS/MS method for simultaneous determination of MTC-220 and its metabolites (paclitaxel and MDA-linker) in dog plasma has been developed and validated. After addition of docetaxel (internal standard), plasma samples containing MTC-220, paclitaxel and MDA-linker were prepared based on a simple protein precipitation by adding two volumes of acetonitrile. The separation was performed on a ZorbaxSB-C18 column (3.5μm, 2.1mm×100mm) at a flow rate of 0.2ml/min, using acetonitrile/water containing 0.1% formic acid (v/v) as mobile phase. The detection was performed on a triple quadrupole tandem mass spectrometer equipped with electrospray ionization (ESI) by selected reaction monitoring (SRM). The MS/MS ion transit ions monitored were 1444.4→623.8 for MTC-220, 876.4→307.9 for paclitaxel, 631.2→531.2 for MDA-linker and 830.2→549.1 for the internal standard. Linear detection responses were obtained for MTC-220, paclitaxel and MDA-linker ranging from 10 to 5000, 5 to 2500 and 5 to 500ng/ml, respectively. The lower limits of quantitation (LLOQs) for MTC-220, paclitaxel and MDA-linker were 10, 5 and 5ng/ml, respectively. The intra-day and inter-day precisions (RSD, %) of the three analytes do not exceed 10.9% except for LLOQs (≤17.50), and the accuracy (RE, %) were within ±17.5% for LLOQs and ±12.6% for the others. The average recoveries of three compounds were greater than 85.0%. The analytes were proved to be stable during all sample storage, preparation and analytic procedures. The validated method was successfully applied to pharmacokinetic studies of MTC-220 and its metabolites in beagle dogs after intravenous infusion of MTC-220 at 2.5mg/kg. Copyright © 2014 Elsevier B.V. All rights reserved.

Seminal Plasma HIV-1 RNA Concentration Is Strongly Associated with Altered Levels of Seminal Plasma Interferon-γ, Interleukin-17, and Interleukin-5

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Hoffman, Jennifer C.; Anton, Peter A.; Baldwin, Gayle Cocita; Elliott, Julie; Anisman-Posner, Deborah; Tanner, Karen; Grogan, Tristan; Elashoff, David; Sugar, Catherine; Yang, Otto O.

2014-01-01

Abstract Seminal plasma HIV-1 RNA level is an important determinant of the risk of HIV-1 sexual transmission. We investigated potential associations between seminal plasma cytokine levels and viral concentration in the seminal plasma of HIV-1-infected men. This was a prospective, observational study of paired blood and semen samples from 18 HIV-1 chronically infected men off antiretroviral therapy. HIV-1 RNA levels and cytokine levels in seminal plasma and blood plasma were measured and analyzed using simple linear regressions to screen for associations between cytokines and seminal plasma HIV-1 levels. Forward stepwise regression was performed to construct the final multivariate model. The median HIV-1 RNA concentrations were 4.42 log10 copies/ml (IQR 2.98, 4.70) and 2.96 log10 copies/ml (IQR 2, 4.18) in blood and seminal plasma, respectively. In stepwise multivariate linear regression analysis, blood HIV-1 RNA level (pplasma HIV-1 RNA level. After controlling for blood HIV-1 RNA level, seminal plasma HIV-1 RNA level was positively associated with interferon (IFN)-γ (p=0.03) and interleukin (IL)-17 (p=0.03) and negatively associated with IL-5 (p=0.0007) in seminal plasma. In addition to blood HIV-1 RNA level, cytokine profiles in the male genital tract are associated with HIV-1 RNA levels in semen. The Th1 and Th17 cytokines IFN-γ and IL-17 are associated with increased seminal plasma HIV-1 RNA, while the Th2 cytokine IL-5 is associated with decreased seminal plasma HIV-1 RNA. These results support the importance of genital tract immunomodulation in HIV-1 transmission. PMID:25209674

Krill protein hydrolysate reduces plasma triacylglycerol level with concurrent increase in plasma bile acid level and hepatic fatty acid catabolism in high-fat fed mice

Directory of Open Access Journals (Sweden)

Marie S. Ramsvik

2013-11-01

Full Text Available Background: Krill powder, consisting of both lipids and proteins, has been reported to modulate hepatic lipid catabolism in animals. Fish protein hydrolysate diets have also been reported to affect lipid metabolism and to elevate bile acid (BA level in plasma. BA interacts with a number of nuclear receptors and thus affects a variety of signaling pathways, including very low density lipoprotein (VLDL secretion. The aim of the present study was to investigate whether a krill protein hydrolysate (KPH could affect lipid and BA metabolism in mice. Method: C57BL/6 mice were fed a high-fat (21%, w/w diet containing 20% crude protein (w/w as casein (control group or KPH for 6 weeks. Lipids and fatty acid composition were measured from plasma, enzyme activity and gene expression were analyzed from liver samples, and BA was measured from plasma. Results: The effect of dietary treatment with KPH resulted in reduced levels of plasma triacylglycerols (TAG and non-esterified fatty acids (NEFAs. The KPH treated mice had also a marked increased plasma BA concentration. The increased plasma BA level was associated with induction of genes related to membrane canalicular exporter proteins (Abcc2, Abcb4 and to BA exporters to blood (Abcc3 and Abcc4. Of note, we observed a 2-fold increased nuclear farnesoid X receptor (Fxr mRNA levels in the liver of mice fed KPH. We also observed increased activity of the nuclear peroxiosme proliferator-activated receptor alpha (PPARα target gene carnitine plamitoyltransferase 2 (CPT-2. Conclusion: The KPH diet showed to influence lipid and BA metabolism in high-fat fed mice. Moreover, increased mitochondrial fatty acid oxidation and elevation of BA concentration may regulate the plasma level of TAGs and NEFAs.

Identification of berberrubine metabolites in rats by using ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry.

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Wang, Kun; Qiao, Miao; Chai, Liwei; Cao, Shijie; Feng, Xinchi; Ding, Liqin; Qiu, Feng

2018-01-01

Berberrubine, an isoquinoline alkaloid isolated from many medicinal plants, possesses diverse pharmacological activities, including glucose-lowering, lipid-lowering, anti-inflammatory, and anti-tumor effects. This study aimed to investigate the metabolic profile of berberrubine in vivo. Therefore, a rapid and reliable method using the ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry (UPLC-Q-TOF-MS) and metabolynx™ software with mass defect filter (MDF) technique was developed. Plasma, bile, urine and feces samples were collected from rats after oral administration of berberrubine with a dose of 30.0mg/kg and analyzed to characterize the metabolites of berberrubine in vivo for the first time. A total of 57 metabolites were identified, including 54 metabolites in urine, 39 metabolites in plasma, 28 metabolites in bile and 18 metabolites in feces. The results indicated that demethylenation, reduction, hydroxylation, demethylation, glucuronidation, and sulfation were the major metabolic pathways of berberrubine in vivo. Copyright © 2017 Elsevier B.V. All rights reserved.

Measurement of operative plasma endotoxin levels in jaundiced and non-jaundiced patients.

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Pain, J A; Bailey, M E

1987-01-01

A study of portal plasma endotoxin levels was performed using a chromogenic limulus amoebocyte lysate (LAL) assay. The assay proved sensitive and reproducible. In only 1 of 25 healthy subjects was the systemic plasma endotoxin level above 100 pg/ml (equivalent Escherichia coli 0111B4). In 30 non-jaundiced patients undergoing surgery the mean (+SEM) portal plasma endotoxin level (60 + 9 pg/ml) was significantly higher (p less than 0.05) than the mean level in the systemic blood (46 + 6 pg/ml), supporting the concept of endotoxin absorption from the intestine into the portal blood. In 20 patients with obstructive jaundice undergoing surgery 42% of portal, 45% of inferior mesenteric and 35% of systemic venous plasma endotoxin levels were above 100 pg/ml. There were significantly higher levels in the portal (p less than 0.05) and inferior mesenteric (p less than 0.05) compared with the systemic blood. Neither the presence of malignancy nor the duration of surgery appeared to influence endotoxin absorption. The significance of raised plasma endotoxin levels in obstructive jaundice is discussed.

Immunoglobulin G levels during collection of large volume plasma for fractionation.

Science.gov (United States)

Burkhardt, Thomas; Rothe, Remo; Moog, Rainer

2017-06-01

There is a need of comprehensive work dealing with the quality of plasma for fractionation with respect to the IgG content as today most plasma derivates are used to treat patients with immunodeficiencies and autoimmune disorders. Therefore, a prospective study was carried out to analyse IgG levels before plasmapheresis and every 200ml collected plasma. Fifty-four experienced plasmapheresis donors were recruited for subsequent 850ml plasmapheresis using the Aurora Plasmapheresis System. Donorś peripheral blood counts were analysed before and after plasmapheresis using an electronic counter. Total protein, IgG and citrate were measured turbidometrically before, during and after apheresis as well as in the plasma product. Furthermore, platelets, red and white blood cells were analysed as parameters of product quality. An average of 2751±247ml blood was processed in 47±6min. The collected plasma volume was 850±1mL and citrate consumption was 177±15mL. A continuous drop of donors' IgG level was observed during plasmapheresis. The drop was 13% of the IgG baseline value at 800mL collected plasma. Total protein, IgG and cell counts of the plasma product met current guidelines of plasma for fractionation. Donors' IgG levels during apheresis showed a steady decrease without compromising the quality of plasma product. Copyright © 2017 Elsevier Ltd. All rights reserved.

Determination of ximelagatran, melagatran and two intermediary metabolites in plasma by mixed-mode solid phase extraction and LC-MS/MS.

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Dunér, Kristina; Bäckström, Jonas; Magnell, Niklas; Svennberg, Henrik; Ahnoff, Martin; Logren, Ulrika

2007-06-01

An analytical method was developed for the determination of ximelagatran, an oral direct thrombin inhibitor, its active metabolite melagatran, and the two intermediate metabolites, OH-melagatran and ethyl-melagatran in human plasma. Extraction of plasma was carried out on a mixed mode bonded sorbent material (C8/SO(3)(-)). All four analytes, including their isotope-labelled internal standards, were eluted at high ionic strength with a mixture of 50% methanol and 50% buffer (0.25 M ammonium acetate and 0.05 M formic acid, pH 5.3) with an extraction recovery above 80%. The extracts were demonstrated to be clean in terms of a low concentration of albumin and lysoPC. The sample extraction was fully automated and performed in 96-well plates using a Tecan Genesis pipetting robot. Analysis of the extracts were performed with liquid chromatography followed by positive electrospray ionization mass spectrometry. The low organic content and the low pH of the extracts allowed for, after dilution 1:3 with buffer, direct injection onto the LC-column. The four analytes were separated on a C18 analytical LC-column using gradient elution with the acetonitrile concentration varying from 10 to 30% (v/v) and the ammonium acetate and acetic acid concentration kept constant at 10 and 5 mmol/L, respectively, at a flow rate of 0.75 mL/min. Linearity was achieved over the calibrated range 0.010-4.0 micromol/L with accuracy and relative standard deviation in the range 96.9-101.2% and 6.6-17.1%, respectively at LLOQ, and in the range 94.7-102.6% and 2.7-6.8%, respectively at concentrations above 3 x LLOQ. The method replaces a manual method, and displays the advantages of having a fully automated sample clean-up, no evaporation/reconstitution step, high recovery, and complete LC-separation of all four analytes.

Decreased plasma levels of the endothelial protective sphingosine-1-phosphate are associated with dengue-induced plasma leakage

NARCIS (Netherlands)

Michels, M.; Japtok, L.; Alisjahbana, B.; Wisaksana, R.; Sumardi, U.; Puspita, M.; Kleuser, B.; Mast, Q. de; Ven, A.J.A.M. van der

2015-01-01

BACKGROUND: A transient endothelial hyperpermeability is a hallmark of severe dengue infections. Sphingosine-1-phosphate (S1P) maintains vascular integrity and protects against plasma leakage. We related plasma S1P levels to dengue-induced plasma leakage and studied mechanisms that may underlie the

Plasma klotho levels decrease in both anorexia nervosa and obesity.

Science.gov (United States)

Amitani, Marie; Asakawa, Akihiro; Amitani, Haruka; Kaimoto, Kaori; Sameshima, Nanami; Koyama, Ken Ichiro; Haruta, Izumi; Tsai, Minglun; Nakahara, Toshihiro; Ushikai, Miharu; Cheng, Kai-Chun; Hamada, Satoshi; Inui, Akio

2013-09-01

The aim of this study was to examine the associations of klotho with body mass index (BMI) in patients with restricting-type anorexia nervosa (r-AN) and obesity. We examined plasma klotho as well as adiponectin and its isoform levels in comparison in 11 obese patients, 12 r-AN patients, and 11 control participants. Plasma klotho levels were markedly lower in the obesity and r-AN groups than in the control group. Moreover, plasma klotho levels increased significantly after the recovery of BMI in r-AN patients. Total and high-molecular-weight adiponectin levels were significantly decreased only in obesity. There was no relationship between klotho and total adiponectin levels or klotho and respective adiponectin isoform levels in the entire study population. These results suggest that klotho may reflect normal nutritional state, and that the decrease of klotho in r-AN and obesity may underlie the deteriorating processes of these disorders. Copyright © 2013 Elsevier Inc. All rights reserved.

Biomarker discovery in biological specimens (plasma, hair, liver and kidney) of diabetic mice based upon metabolite profiling using ultra-performance liquid chromatography with electrospray ionization time-of-flight mass spectrometry.

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Tsutsui, Haruhito; Maeda, Toshio; Min, Jun Zhe; Inagaki, Shinsuke; Higashi, Tatsuya; Kagawa, Yoshiyuki; Toyo'oka, Toshimasa

2011-05-12

The number of diabetic patients has recently been increasing worldwide. Diabetes is a multifactorial disorder based on environmental factors and genetic background. In many cases, diabetes is asymptomatic for a long period and the patient is not aware of the disease. Therefore, the potential biomarker(s), leading to the early detection and/or prevention of diabetes mellitus, are strongly required. However, the diagnosis of the prediabetic state in humans is a very difficult issue, because the lifestyle is variable in each person. Although the development of a diagnosis method in humans is the goal of our research, the extraction and structural identification of biomarker candidates in several biological specimens (i.e., plasma, hair, liver and kidney) of ddY strain mice, which undergo naturally occurring diabetes along with aging, were carried out based upon a metabolite profiling study. The low-molecular-mass compounds including metabolites in the biological specimens of diabetic mice (ddY-H) and normal mice (ddY-L) were globally separated by ultra-performance liquid chromatography (UPLC) using different reversed-phase columns (i.e., T3-C18 and HS-F5) and detected by electrospray ionization time-of-flight mass spectrometry (ESI-TOF-MS). The biomarker candidates related to diabetes mellitus were extracted from a multivariate statistical analysis, such as an orthogonal partial least-squares-discriminant analysis (OPLS-DA), followed by a database search, such as ChemSpider, KEGG and HMDB. Many metabolites and unknown compounds in each biological specimen were detected as the biomarker candidates related to diabetic mellitus. Among them, the elucidation of the chemical structures of several possible metabolites, including more than two biological specimens, was carried out along with the comparison of the tandem MS/MS analyses using authentic compounds. One metabolite was clearly identified as N-acetyl-L-leucine based upon the MS/MS spectra and the retention time on

Plasma levels of gastrointestinal regulatory peptides in patients receiving maintenance hemodialysis

International Nuclear Information System (INIS)

Hegbrant, J.; Thysell, H.; Ekmann, R.

1991-01-01

The fasting plasma levels of nine gastrointestinal regulatory peptides were measured by radioimmunoassay in 13 stable patients with chronic renal failure, receiving hemodialysis treatment regularly and compared with those of ten healthy controls. The plasma concentrations of gastrin-releasing peptide, motilin, neurotensin, pancreatic polypeptide, peptide YY, somatostatin, substance P, and vasoactive intestinal peptide were increased. The plasma level of gastrin was not statistically different from that of the control (p=0.077). It is concluded that patients with chronic renal failure, receiving hemodialysis treatment regularly, have increased concentrations of eight of nine measured gastrointestinal regulatory peptides. The elevated levels of gastrointestinal peptides in patients with chronic renal failure may contribute to uremic gastrointestinal symptoms and dysfunctions. It is necessary to make a renal function evaluation before interpreting measured plasma levels of gastrointestinal regulatory peptides. 62 refs., 2 tabs

Clinical value of plasma endothelin levels in children with cardiovascular diseases

International Nuclear Information System (INIS)

Chen Nianfa; Duan Yongqiang

2009-01-01

To explore the clinical value of plasma endothelin (ET-1) levels in children with cardiovascular diseases, 77 children with heart failure, obesity, hyperlipemia, fatty liver and hypertension were divided into 5 experimental groups and 21 health children with same age and gender as control group. The plasma levels of ET-1 in these children were tested by RIA. The results showed that plasma levels of ET-1 in 5 experimental groups were 112.8 ± 34.1ng/L, 57.8 ± 19.1ng/L,64.5 ± 25.3ng/L, 74.9 ± 28.4ng/L and 60.7 ± 21.6ng/L, respectively. The ET-1 levels in 5 groups were significantly higher than that in control group (P<0.01). The results indicate the higher plasma ET-1 levels in children are related with cardiovascular diseases, and it is useful in the diagnosis of children cardiovascular diseases. (authors)

Plasma metabolic changes in Chinese HIV-infected patients receiving lopinavir/ritonavir based treatment: Implications for HIV precision therapy.

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Li, Xiaolin; Wu, Tong; Jiang, Yongjun; Zhang, Zining; Han, Xiaoxu; Geng, Wenqing; Ding, Haibo; Kang, Jing; Wang, Qi; Shang, Hong

2018-05-16

The goal of this study is to profile the metabolic changes in the plasma of HIV patients receiving lopinavir/ritonavir (LPV/r)-based highly active antiretroviral therapy (HAART) relative to their treatment-naïve phase, aimed to identify precision therapy for HIV for improving prognosis and predicting dyslipidemia caused by LPV/r. 38 longitudinal plasma samples were collected from 19 HIV-infected patients both before and after antiretroviral therapy, and 18 samples from healthy individuals were used as controls. Untargeted metabolomics profiling of these plasma samples was performed using liquid chromatography-mass spectrometry (LC-MS) and gas chromatography-mass spectrometry (GC-MS). A total of 331 compounds of known identity were detected among these metabolites, a 67-metabolite signature mainly mapping to tryptophan, histidine, acyl carnitine, ketone bodies and fatty acid metabolism distinguished HIV patients from healthy controls. The levels of 19 out of the 67 altered metabolites including histidine, kynurenine, and 3-hydroxybutyrate (BHBA), recovered after LPV/r-based antiretroviral therapy, and histidine was positively correlated with the presence of CD4 + T lymphocytes. Furthermore, using receiver operating characteristic (ROC) analyses, we discovered that butyrylcarnitine in combination with myristic acid from plasma in treatment-naïve patients could predict dyslipidemia caused by LPV/r with 87% accuracy. Metabolites alterations in treatment-naïve HIV patients may indicate an inflammatory, oxidative state and mitochondrial dysfunction that is permissive for disease progression. Histidine may provide a specific protective function for HIV patients. Besides, elevated fatty acids levels including butyrylcarnitine and myristic acid after infection may indicate patients at risk of suffering from dyslipidemia after LPV/r-based HAART. Copyright © 2018 Elsevier Ltd. All rights reserved.

Plasma progesterone levels in progesterone treated cows

International Nuclear Information System (INIS)

Grosskopf, J.F.W.; Van Niekerk, C.H.; Morgenthal, J.C.

1979-01-01

A technique for the radioimmunoassay of progesterone in plasma is described. In one trial the oestrous cycles of four cycling cows and in another trial of one non-cycling cow and two cycling heifers were synchronized by the administration of progesterone. Each female received either 50 mg or 0,1 mg/kg of progesterone intramuscularly on alternate days in two courses of four and six injections respectively. Blood samples of the animals were collected either daily or two-daily before, over the entire period of treatment and for eight days after the last progesterone injection. The results of the progesterone assays are represented graphically for each individual cow or heifer. The plasma progesterone levels during treatment were maintained reasonably well at levels corresponding to those normally encountered during the luteal phase of the cycle. The progesterone levels, however, did not drop as rapidly as desired after the last injection but might have been influenced by a residual corpus luteum from a previous ovulation

Rationalization and prediction of in vivo metabolite exposures: The role of metabolite kinetics, clearance predictions and in vitro parameters

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Lutz, Justin D.; Fujioka, Yasushi; Isoherranen, Nina

2010-01-01

Importance of the field Due to growing concerns over toxic or active metabolites, significant efforts have been focused on qualitative identification of potential in vivo metabolites from in vitro data. However, limited tools are available to quantitatively predict their human exposures. Areas covered in this review Theory of clearance predictions and metabolite kinetics is reviewed together with supporting experimental data. In vitro and in vivo data of known circulating metabolites and their parent drugs was collected and the predictions of in vivo exposures of the metabolites were evaluated. What the reader will gain The theory and data reviewed will be useful in early identification of human metabolites that will circulate at significant levels in vivo and help in designing in vivo studies that focus on characterization of metabolites. It will also assist in rationalization of metabolite-to-parent ratios used as markers of specific enzyme activity. Take home message The relative importance of a metabolite in comparison to the parent compound as well as other metabolites in vivo can only be predicted using the metabolites in vitro formation and elimination clearances, and the in vivo disposition of a metabolite can only be rationalized when the elimination pathways of that metabolite are known. PMID:20557268

Androgen and androgen metabolite levels in serum and urine of East African chimpanzees (Pan troglodytes schweinfurthii): comparison of EIA and LC-MS analyses.

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Preis, Anna; Mugisha, Lawrence; Hauser, Barbara; Weltring, Anja; Deschner, Tobias

2011-12-01

The primary male androgen testosterone (T) is often used as an endocrinological marker to investigate androgen-behaviour interactions in males. In chimpanzees and bonobos, studies investigating the relationship between T levels and dominance rank or aggressive behaviour have revealed contradictory results. The immunoassays used in these studies were originally developed for the measurement of steroids in serum. Their application to non-invasively collected samples, however, can lead to methodological problems due to cross-reacting metabolites, which might occur in urine or faeces but not in blood. The overall aim of this study, therefore, is to clarify whether a T enzyme immunoassay (EIA) is an applicable method to monitor testicular function in adult male chimpanzees. To estimate the impact of cross-reacting androgens on the used T EIA, we compared the results of an EIA measurement with a set of androgen metabolite levels measured by LC-MS. In urine from male chimpanzees, cross-reactivities appear to exist mainly with T and its exclusive metabolites, 5α-dihydrotestosterone (5α-DHT) and 5α-androstanediol (androstanediol). Both urinary and serum T levels of male chimpanzees were significantly higher than female T levels when measured with the T EIA, indicating a reliable measurement of testicular androgens and their exclusive metabolites with the used EIA. In urine from female chimpanzees, the comparison between LC-MS and T EIA results indicated a higher impact of cross-reactions with adrenal androgen metabolites. Therefore, the investigation of urinary T levels in female chimpanzees with a T EIA seems to be problematic. Overall our results show that a T EIA can be a reliable method to monitor testicular function in male chimpanzee urine and that LC-MS is a valuable tool for the validation of immunoassays. Copyright © 2011 Elsevier Inc. All rights reserved.

Investigation of metabolites for estimating blood deposition time.

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Lech, Karolina; Liu, Fan; Davies, Sarah K; Ackermann, Katrin; Ang, Joo Ern; Middleton, Benita; Revell, Victoria L; Raynaud, Florence J; Hoveijn, Igor; Hut, Roelof A; Skene, Debra J; Kayser, Manfred

2018-01-01

Trace deposition timing reflects a novel concept in forensic molecular biology involving the use of rhythmic biomarkers for estimating the time within a 24-h day/night cycle a human biological sample was left at the crime scene, which in principle allows verifying a sample donor's alibi. Previously, we introduced two circadian hormones for trace deposition timing and recently demonstrated that messenger RNA (mRNA) biomarkers significantly improve time prediction accuracy. Here, we investigate the suitability of metabolites measured using a targeted metabolomics approach, for trace deposition timing. Analysis of 171 plasma metabolites collected around the clock at 2-h intervals for 36 h from 12 male participants under controlled laboratory conditions identified 56 metabolites showing statistically significant oscillations, with peak times falling into three day/night time categories: morning/noon, afternoon/evening and night/early morning. Time prediction modelling identified 10 independently contributing metabolite biomarkers, which together achieved prediction accuracies expressed as AUC of 0.81, 0.86 and 0.90 for these three time categories respectively. Combining metabolites with previously established hormone and mRNA biomarkers in time prediction modelling resulted in an improved prediction accuracy reaching AUCs of 0.85, 0.89 and 0.96 respectively. The additional impact of metabolite biomarkers, however, was rather minor as the previously established model with melatonin, cortisol and three mRNA biomarkers achieved AUC values of 0.88, 0.88 and 0.95 for the same three time categories respectively. Nevertheless, the selected metabolites could become practically useful in scenarios where RNA marker information is unavailable such as due to RNA degradation. This is the first metabolomics study investigating circulating metabolites for trace deposition timing, and more work is needed to fully establish their usefulness for this forensic purpose.

Diagnosing impaired glucose tolerance using direct infusion mass spectrometry of blood plasma.

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Petr G Lokhov

Full Text Available The goal of this study was to evaluate the capacity for mass spectrometry of blood plasma to diagnose impaired glucose tolerance (IGT. For this study, blood plasma samples from control subjects (n = 30 and patients with IGT (n = 20 were treated with methanol and low molecular weight fraction were then analyzed by direct infusion mass spectrometry. A total of 51 metabolite ions strongly associated with IGT were detected. The area under a receiver operating characteristic (ROC curve (AUC for diagnosing IGT that was based on an analysis of all these metabolites was 0.93 (accuracy 90%, specificity 90%, and sensitivity 90%. The associated reproducibility was 85%. The metabolites identified were also consistent with risk factors previously associated with the development of diabetes. Thus, direct infusion mass spectrometry of blood plasma metabolites represents a rapid, single-step, and reproducible method for the analysis of metabolites. Moreover, this method has the potential to serve as a prototype for clinical analyses that could replace the currently used glucose tolerance test with a more patient-friendly assay.

An Atmospheric Pressure Chemical Ionization MS/MS Assay Using Online Extraction for the Analysis of 11 Cannabinoids and Metabolites in Human Plasma and Urine.

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Klawitter, Jelena; Sempio, Cristina; Mörlein, Sophie; De Bloois, Erik; Klepacki, Jacek; Henthorn, Thomas; Leehey, Maureen A; Hoffenberg, Edward J; Knupp, Kelly; Wang, George S; Hopfer, Christian; Kinney, Greg; Bowler, Russell; Foreman, Nicholas; Galinkin, Jeffrey; Christians, Uwe; Klawitter, Jost

2017-10-01

Although, especially in the United States, there has been a recent surge of legalized cannabis for either recreational or medicinal purposes, surprisingly little is known about clinical dose-response relationships, pharmacodynamic and toxicodynamic effects of cannabinoids such as Δ9-tetrahydrocannabinol (THC). Even less is known about other active cannabinoids. To address this knowledge gap, an online extraction, high-performance liquid chromatography coupled with tandem mass spectrometry method for simultaneous quantification of 11 cannabinoids and metabolites including THC, 11-hydroxy-Δ9-tetrahydrocannabinol, 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid, 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid glucuronide (THC-C-gluc), cannabinol, cannabidiol, cannabigerol, cannabidivarin, Δ9-tetrahydrocannabivarin (THCV), and 11-nor-9-carboxy-Δ9-tetrahydrocannabivarin (THCV-COOH) was developed and validated in human urine and plasma. In contrast to atmospheric pressure chemical ionization, electrospray ionization was associated with extensive ion suppression in plasma and urine samples. Thus, the atmospheric pressure chemical ionization assay was validated showing a lower limit of quantification ranging from 0.39 to 3.91 ng/mL depending on study compound and matrix. The upper limit of quantification was 400 ng/mL except for THC-C-gluc with an upper limit of quantification of 2000 ng/mL. The linearity was r > 0.99 for all analyzed calibration curves. Acceptance criteria for intrabatch and interbatch accuracy (85%-115%) and imprecision (<15%) were met for all compounds. In plasma, the only exceptions were THCV (75.3%-121.2% interbatch accuracy) and cannabidivarin (interbatch imprecision, 15.7%-17.2%). In urine, THCV did not meet predefined acceptance criteria for intrabatch accuracy. This assay allows for monitoring not only THC and its major metabolites but also major cannabinoids that are of interest for marijuana research and clinical practice.

Plasma Folate and Vitamin B12 Levels in Patients with Hepatocellular Carcinoma

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Lian-Hua Cui

2016-06-01

Full Text Available Folate and vitamin B12 involved in the one-carbon metabolism may play a key role in carcinogenesis and progression of hepatocellular carcinoma (HCC through influencing DNA integrity. The purpose of this study is to evaluate the association of plasma folate and vitamin B12 levels with HCC in a case-control study on 312 HCC patients and 325 cancer-free controls. Plasma concentrations of folate and vitamin B12 in all the subjects were measured by electrochemiluminescence immunoassay. Meanwhile, the information of HCC patients’ clinical characteristics including tumor-node-metastasis (TNM stage, tumor size and tumor markers were collected. The patients of HCC had significantly lower folate levels than those of controls; there was no significant difference in the mean of plasma vitamin B12 levels. We also observed an inverse association between the levels of plasma folate and HCC: the adjusted odds ratios (OR (95% confidence intervals (CI of HCC from the highest to lowest quartile of folate were 0.30 (0.15–0.60, 0.33 (0.17–0.65, and 0.19 (0.09–0.38. Compared to the subjects in the lowest quartile of plasma vitamin B12, only the subjects in the highest quartile of vitamin B12 exhibited a significant positive relationship with HCC, the adjusted OR was 2.01 (95% CI, 1.02–3.98. HCC patients with Stage III and IV or bigger tumor size had lower folate and higher vitamin B12 levels. There was no significant difference in the mean plasma folate levels of the HCC cases in tumor markers status (AFP, CEA and CA19-9 levels, whereas patients with higher CEA or CA19-9 levels retained significantly more plasma vitamin B12 than those with normal-CEA or CA19-9 level. In conclusion, plasma folate and vitamin B12 levels could be associated with HCC, and might be used as predictors of clinical characteristics of HCC patients. However, further prospective studies are essential to confirm the observed results.

Simultaneous determination of tryptophan and 8 metabolites in human plasma by liquid chromatography/tandem mass spectrometry.

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Boulet, Lysiane; Faure, Patrice; Flore, Patrice; Montérémal, Julien; Ducros, Véronique

2017-06-01

Tryptophan (Trp) is an essential amino-acid and the precursor of many biologically active substances such as kynurenine (KYN) and serotonin (5HT). Its metabolism is involved in different physiopathological states, such as cardiovascular diseases, cancer, immunomodulation or depression. Hence, the quantification of Trp catabolites, from both KYN and 5HT pathways, might be usefulfor the discovery of novel diagnostic and follow-up biomarkers. We have developed a simple method for quantification of Trp and 8 of its metabolites,involved in both KYN and 5HT pathways, using liquid chromatography coupled to tandem mass spectrometry. We also validated the methodin human plasma samples, according to NF EN ISO 15189 criteria. Our method shows acceptable intra- and inter-day coefficients of variation (CV) (<12% and <16% respectively). The linearity entirelycovers the human plasma range. Stabilities of whole blood and of residues weredetermined, as well as the use of 2 different types of collectiontube, enabling us to adapt our process. Matrix effects and reference values showed good agreement compared to the literature. We propose here a method allowing the simultaneous quantification of a panel of Trp catabolites, never used before to our knowledge. This method, witha quickchromatographic runtime (15min) and simple sample preparation, has beenvalidated according to NF EN ISO 15189 criteria. The method enables the detailed analysis of these metabolic pathways, which are thought to be involved in a number of pathological conditions. Copyright © 2017 Elsevier B.V. All rights reserved.

Online restricted-access material combined with high-performance liquid chromatography and tandem mass spectrometry for the simultaneous determination of vanillin and its vanillic acid metabolite in human plasma.

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Li, De-Qiang; Zhang, Zhi-Qing; Yang, Xiu-Ling; Zhou, Chun-Hua; Qi, Jin-Long

2016-09-01

An automated online solid-phase extraction with restricted-access material combined with high-performance liquid chromatography and tandem mass spectrometry was developed and validated for the simultaneous quantification of vanillin and its vanillic acid metabolite in human plasma. After protein precipitation by methanol, which contained the internal standards, the supernatant of plasma samples was injected to the system, the endogenous large molecules were flushed out, and target analytes were trapped and enriched on the adsorbent, resulting in a minimization of sample complexity and ion suppression effects. Calibration curves were linear over the concentrations of 5-1000 ng/mL for vanillin and 10-5000 ng/mL for vanillic acid with a coefficient of determination >0.999 for the determined compounds. The lower limits of quantification of vanillin and vanillic acid were 5.0 and 10.0 ng/mL, respectively. The intra- and inter-run precisions expressed as the relative standard deviation were 2.6-8.6 and 3.2-10.2%, respectively, and the accuracies expressed as the relative error were in the range of -6.1 to 7.3%. Extraction recoveries of analytes were between 89.5 and 97.4%. There was no notable matrix effect for any analyte concentration. The developed method was proved to be sensitive, repeatable, and accurate for the quantification of vanillin and its vanillic acid metabolite in human plasma. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Plasma Orexin-A Levels in COPD Patients with Hypercapnic Respiratory Failure

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Lin-Yun Zhu

2011-01-01

Full Text Available Orexins have previously been shown to promote wakefulness, regulate lipid metabolism and participate in energy homeostasis. The aim of the study was to determine the relationship between plasma orexin-A and body composition in COPD in-patients with hypercapnic respiratory failure. 40 patients with hypercapnic respiratory failure and 22 healthy individuals were enrolled prospectively in this study. Plasma orexin-A levels, BMI, SaO2, PaCO2 and PaO2 were noted for all the patients. Plasma orexin-A levels were higher in the underweight (UW group, normal weight (NW group and overweight (OW group of COPD patients as compared with UW, NW and OW group of the control group (P<.05. Plasma orexin-A in COPD patients were higher in the OW group than in the NW group and the UW group. Plasma orexin-A levels showed significant correlation with body mass index (BMI, independent of PaO2 (r=0.576; P<.05 and %fat (r=0.367; P<.05; a negative correlation was noted between plasma orexin-A levels and PaO2 (r=−0.738; P<.05 and SaO2 (r=−0.616; P<.05. Our results suggest that orexin-A levels are high in COPD patients with hypercapnic respiratory failure, and vary according to BMI and body composition. Orexin-A may be associated with the severity of hypoxemia in COPD patients with hypercapnic respiratory failure.

Choline and Choline Metabolite Patterns and Associations in Blood and Milk during Lactation in Dairy Cows

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Artegoitia, Virginia M.; Middleton, Jesse L.; Harte, Federico M.; Campagna, Shawn R.; de Veth, Michael J.

2014-01-01

Milk and dairy products are an important source of choline, a nutrient essential for human health. Infant formula derived from bovine milk contains a number of metabolic forms of choline, all contribute to the growth and development of the newborn. At present, little is known about the factors that influence the concentrations of choline metabolites in milk. The objectives of this study were to characterize and then evaluate associations for choline and its metabolites in blood and milk through the first 37 weeks of lactation in the dairy cow. Milk and blood samples from twelve Holstein cows were collected in early, mid and late lactation and analyzed for acetylcholine, free choline, betaine, glycerophosphocholine, lysophosphatidylcholine, phosphatidylcholine, phosphocholine and sphingomyelin using hydrophilic interaction liquid chromatography-tandem mass spectrometry, and quantified using stable isotope-labeled internal standards. Total choline concentration in plasma, which was almost entirely phosphatidylcholine, increased 10-times from early to late lactation (1305 to 13,535 µmol/L). In milk, phosphocholine was the main metabolite in early lactation (492 µmol/L), which is a similar concentration to that found in human milk, however, phosphocholine concentration decreased exponentially through lactation to 43 µmol/L in late lactation. In contrast, phosphatidylcholine was the main metabolite in mid and late lactation (188 µmol/L and 659 µmol/L, respectively), with the increase through lactation positively correlated with phosphatidylcholine in plasma (R 2 = 0.78). Unlike previously reported with human milk we found no correlation between plasma free choline concentration and milk choline metabolites. The changes in pattern of phosphocholine and phosphatidylcholine in milk through lactation observed in the bovine suggests that it is possible to manufacture infant formula that more closely matches these metabolites profile in human milk. PMID:25157578

Choline and choline metabolite patterns and associations in blood and milk during lactation in dairy cows.

Directory of Open Access Journals (Sweden)

Virginia M Artegoitia

Full Text Available Milk and dairy products are an important source of choline, a nutrient essential for human health. Infant formula derived from bovine milk contains a number of metabolic forms of choline, all contribute to the growth and development of the newborn. At present, little is known about the factors that influence the concentrations of choline metabolites in milk. The objectives of this study were to characterize and then evaluate associations for choline and its metabolites in blood and milk through the first 37 weeks of lactation in the dairy cow. Milk and blood samples from twelve Holstein cows were collected in early, mid and late lactation and analyzed for acetylcholine, free choline, betaine, glycerophosphocholine, lysophosphatidylcholine, phosphatidylcholine, phosphocholine and sphingomyelin using hydrophilic interaction liquid chromatography-tandem mass spectrometry, and quantified using stable isotope-labeled internal standards. Total choline concentration in plasma, which was almost entirely phosphatidylcholine, increased 10-times from early to late lactation (1305 to 13,535 µmol/L. In milk, phosphocholine was the main metabolite in early lactation (492 µmol/L, which is a similar concentration to that found in human milk, however, phosphocholine concentration decreased exponentially through lactation to 43 µmol/L in late lactation. In contrast, phosphatidylcholine was the main metabolite in mid and late lactation (188 µmol/L and 659 µmol/L, respectively, with the increase through lactation positively correlated with phosphatidylcholine in plasma (R2 = 0.78. Unlike previously reported with human milk we found no correlation between plasma free choline concentration and milk choline metabolites. The changes in pattern of phosphocholine and phosphatidylcholine in milk through lactation observed in the bovine suggests that it is possible to manufacture infant formula that more closely matches these metabolites profile in human milk.

L-carnitine plasma levels in dogs and cats. A diagnostic parameter?

International Nuclear Information System (INIS)

Fischer, J.

1993-04-01

The relation between levels of carnitine in plasma and lesions of organs should be demonstrated. 52 dogs and 58 cats examined in veterinary clinics for several reasons and routinely screened for blood chemistry also were analysed for free plasma carnitine by a radiocarbon method. Increased carnitine levels were observed in both species in case of heart, liver and kidney disorders. Additionally the influence of food intake on carnitine levels in dogs was studied. Postprandial changes were insignificant. Because of lack of information about carnitine levels in cats and changes with age plasma carnitine was determined in cats and kittens. The range of normal values was 8.2 to 24.2 μmol/l without any significance of age

Normal fasting plasma glucose levels and type 2 diabetes in young men.

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Tirosh, Amir; Shai, Iris; Tekes-Manova, Dorit; Israeli, Eran; Pereg, David; Shochat, Tzippora; Kochba, Ilan; Rudich, Assaf

2005-10-06

The normal fasting plasma glucose level was recently defined as less than 100 mg per deciliter (5.55 mmol per liter). Whether higher fasting plasma glucose levels within this range independently predict type 2 diabetes in young adults is unclear. We obtained blood measurements, data from physical examinations, and medical and lifestyle information from men in the Israel Defense Forces who were 26 to 45 years of age. A total of 208 incident cases of type 2 diabetes occurred during 74,309 person-years of follow-up (from 1992 through 2004) among 13,163 subjects who had baseline fasting plasma glucose levels of less than 100 mg per deciliter. A multivariate model, adjusted for age, family history of diabetes, body-mass index, physical-activity level, smoking status, and serum triglyceride levels, revealed a progressively increased risk of type 2 diabetes in men with fasting plasma glucose levels of 87 mg per deciliter (4.83 mmol per liter) or more, as compared with those whose levels were in the bottom quintile (less than 81 mg per deciliter [4.5 mmol per liter], P for trend <0.001). In multivariate models, men with serum triglyceride levels of 150 mg per deciliter (1.69 mmol per liter) or more, combined with fasting plasma glucose levels of 91 to 99 mg per deciliter (5.05 to 5.50 mmol per liter), had a hazard ratio of 8.23 (95 percent confidence interval, 3.6 to 19.0) for diabetes, as compared with men with a combined triglyceride level of less than 150 mg per deciliter and fasting glucose levels of less than 86 mg per deciliter (4.77 mmol per liter). The joint effect of a body-mass index (the weight in kilograms divided by the square of the height in meters) of 30 or more and a fasting plasma glucose level of 91 to 99 mg per deciliter resulted in a hazard ratio of 8.29 (95 percent confidence interval, 3.8 to 17.8), as compared with a body-mass index of less than 25 and a fasting plasma glucose level of less than 86 mg per deciliter. Higher fasting plasma glucose

Sensitive method for the quantitative determination of proguanil and its metabolites in rat blood and plasma by liquid chromatography-mass spectrometry.

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Leveque, Nathalie L; Charman, William N; Chiu, Francis C K

2006-01-18

A sensitive, simple and fast liquid chromatography tandem mass spectrometry (HPLC-MS/MS) method for the determination of proguanil (PG) and its metabolites, cycloguanil (CG) and 1-(4-chlorophenyl)biguanide (4CPB), was developed and validated over a concentration range of 1-2000 ng/mL using only 50 microL of blood or plasma. After a simple solvent precipitation procedure, the supernatant was analysed directly by HPLC-MS/MS. Separation was achieved using an ethyl-linked phenyl reverse phase column with polar endcapping with an acetonitrile-water-formic acid gradient. Mass spectrometry was performed using a triple quadrupole mass spectrometer operating in positive electrospray ionization mode. The elution of PG (254.07-->169.99), CG (252.12-->195.02) and 4CPB (212.06-->153.06) was monitored using selected reaction monitoring. The three compounds and the internal standard (chloroproguanil) were well separated by HPLC and no interfering peaks were detected at the usual concentrations found in blood and plasma. The limit of quantification of PG and CG was 1 ng/mL and 5 ng/mL for 4CPB in rat blood and plasma. The extraction efficiency of PG, CG and 4CPB from rat blood and plasma was higher than 73%. The intra- and inter-assay variability of PG, CG and 4CPB were within 12% and the accuracy within +/-5%. This new assay offers higher sensitivity and a much shorter run time over earlier methods.

Serum Reactive Oxygen Metabolite Levels Predict Severe Exacerbations of Asthma

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Nakamoto, Keitaro; Watanabe, Masato; Sada, Mitsuru; Inui, Toshiya; Nakamura, Masuo; Honda, Kojiro; Wada, Hiroo; Mikami, Yu; Matsuzaki, Hirotaka; Horie, Masafumi; Noguchi, Satoshi; Yamauchi, Yasuhiro; Koyama, Hikari; Kogane, Toshiyuki; Kohyama, Tadashi; Takizawa, Hajime

2016-01-01

Background and Purpose Bronchial asthma (BA) is a chronic airway disease characterized by airway hyperresponsiveness and remodeling, which are intimately linked to chronic airway inflammation. Reactive oxygen species (ROS) such as hydrogen peroxide are generated by inflammatory cells that are involved in the pathogenesis of BA. However, the role of ROS in the management of BA patients is not yet clear. We attempted to determine the role of ROS as a biomarker in the clinical setting of BA. Subjects and Methods We enrolled patients with BA from 2013 through 2015 and studied the degrees of asthma control, anti-asthma treatment, pulmonary function test results, fractional exhaled nitric oxide (FeNO), serum reactive oxygen metabolite (ROM) levels, and serum levels of interleukin (IL)-6 and IL-8. Results We recruited 110 patients with BA. Serum ROM levels correlated with white blood cell (WBC) count (rs = 0.273, p = 0.004), neutrophil count (rs = 0.235, p = 0.014), CRP (rs = 0.403, p < 0.001), and IL-6 (rs = 0.339, p < 0.001). Serum ROM levels and IL-8 and CRP levels negatively correlated with %FEV1 (rs = -0.240, p = 0.012, rs = -0.362, p < 0.001, rs = -0.197, p = 0.039, respectively). Serum ROM levels were significantly higher in patients who experienced severe exacerbation within 3 months than in patients who did not (339 [302–381] vs. 376 [352–414] CARR U, p < 0.025). Receiver-operating characteristics analysis showed that ROM levels correlated significantly with the occurrence of severe exacerbation (area under the curve: 0.699, 95% CI: 0.597–0.801, p = 0.025). Conclusions Serum levels of ROM were significantly associated with the degrees of airway obstruction, WBC counts, neutrophil counts, IL-6, and severe exacerbations. This biomarker may be useful in predicting severe exacerbations of BA. PMID:27776186

Effects of Rakkyofructan on Postprandial Glucose Level in Plasma

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谷, 政八; 池田, 涼子; 谷, 洋子; 小林, 恭一; Tani, Masahachi; Ikeda, Ryouko; Tani, Hiroko; Kobayashi, Kyoichi

2010-01-01

The effect of Rakkyofructan on the glucose level in plasma after intake of high carbohydrate diet was investigated.The six healthy female volunteers consumed 50 g of carbohydrate meal (the glucose, the cooked white rice, the bread, or the cooked sweet potato) with or without Rakkyofructan.Blood specimen was collected of before and 30, 45, 60, 90, 120 and 150 min after intake, and the glucose level in plasma was measured.The peak value (Cmax) and the area under curve (AUC) of blood glucose lev...

Determination of psilocin, bufotenine, LSD and its metabolites in serum, plasma and urine by SPE-LC-MS/MS.

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Martin, Rafaela; Schürenkamp, Jennifer; Gasse, Angela; Pfeiffer, Heidi; Köhler, Helga

2013-05-01

A validated method for the simultaneous determination of psilocin, bufotenine, lysergic acid diethylamide and its metabolites in serum, plasma and urine using liquid chromatography-electrospray ionization/tandem mass spectrometry was developed. During the solid-phase extraction procedure with polymeric mixed-mode cation exchange columns, the unstable analytes were protected by ascorbic acid, drying with nitrogen and exclusion of light. The limits of detection and quantitation for all analytes were low. Recovery was ≥86 % for all analytes and no significant matrix effects were observed. Interday and intraday imprecisions at different concentrations ranged from 1.1 to 8.2 % relative standard deviation, bias was within ±5.3 %. Processed samples were stable in the autosampler for at least 2 days. Furthermore, freeze/thaw and long-term stability were investigated. The method was successfully applied to authentic serum and urine samples.

Catecholamine levels in the brain of rats exposed by inhalation to benzalkonium chloride.

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Swiercz, Radosław; Grzelińska, Zofia; Gralewicz, Sławomir; Wasowicz, Wojciech

2009-01-01

The aim of the study was to obtain quantitative data on the effect of inhalation exposure to benzalkonium chloride (BAC) on the concentration of catecholamines and their metabolites in selected brain structures. Additionally, concentration of corticosterone (CORT) in plasma was estimated. Wistar rats were subjected to a single (6-hour) or repeated (3 days, 6 h/day) exposure to BAC aerosol at ca. 30 mg/m3. The Waters integrated analytical system of HPLC was used to determine the plasma corticosterone. Qualitative and quantitative determinations of catecholamines and their metabolites: 3,4-dihydroxyphenylacetic (DOPAC) and homovanillic (HVA) acids were performed with the use of the Waters integrity HPLC. The determinations have shown that in the BAC-exposed rats the plasma CORT concentration was several times higher than in the control rats. A significant increase of the concentration of dopamine (DA) (striatum and diencephalon) and noradrenaline (NA) (hippocampus and cerebellum) and a significant reduction of adrenaline (A) level (cortex, hippocampus, striatum and mesencephaloon) was found to occur in the brain of rats exposed to BAC compared to control. In the animals exposed to BAC, the concentration of DOPAC, a DA metabolite, was significantly reduced, but the change occurred mainly in the striatum. This resulted in a significant decrease of the DOPAC/DA and HVA/DA metabolic ratio in this structure. It is assumed that the alterations in the concentration of catecholamines and their metabolites in the BAC-exposed rats were related to the unexpectedly strong and persistent activation of the hypothalamo-pituitary-adrenocortical (HPA) axis evidenced by the high plasma CORT concentration.

Clinical significance of measurement of plasma homocysteine (Hcy) levels in patients with hepatic cirrhosis

International Nuclear Information System (INIS)

Wu Jiaming

2006-01-01

Objective: To investigate the correlationship between the plasma homocysteine (Hcy) levels and development of hepatic cirrhosis as well as the diagnostic value of plasma Hcy determination. Method: Plasma Hcy levels were measured with ELISA in: (1) 64 patients with post-hepatitis cirrhosis (2) 42 patients with various types of hepatitis but no cirrhosis and (3) 60 controls. Results: The plasma levels of Hcy in patients with cirrhosis were significantly higher than those in the other two groups (P<0.01). The plasma Hcy levels in cirrhotic patients were well correlated with the levels of other hepatic fibrosis markers such as hyaluronic acid and laminin (r=0.87 and r=0.88 respectively, P<0.01), but were not correlated with cholesterol, triglyceride and HDL levels. Conclusion: Plasma Hcy levels was markedly elevated in cirrhotic patients and might be taken as a diagnostic marker. (authors)

Repeated topical treatment, in contrast to single oral doses, with Vitamin A-containing preparations does not affect plasma concentrations of retinol, retinyl esters or retinoic acids in female subjects of child-bearing age

NARCIS (Netherlands)

Nohynek, G.J.; Meuling, W.J.A.; Vaes, W.H.J.; Lawrence, R.S.; Shapiro, S.; Schulte, S.; Steiling, W.; Bausch, J.; Gerber, E.; Sasa, H.; Nau, H.

2006-01-01

Background: Vitamin A is widely used in cosmetic preparations. Given that oral Vitamin A and its metabolites present a potential reproductive risk, the present study investigated the effect of topical Vitamin A on human endogenous plasma levels of Vitamin A and its metabolites. Methods: Two groups

Plasma levels and symptom complaints in patients maintained on daily dosage of methadone hydrochloride.

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Horns, W H; Rado, M; Goldstein, A

1975-06-01

Plasma methadone levels, symptom complaints, and urine tests for illicit opiate use were followed weekly in 17 patients on a methadone maintenance program. There were very large differences between patients in the plasma level established at a given dosage, implying large differences in the rate of methadone metabolism. Despite virtually constant daily dosage, the plasma methadone levels fluctuated greatly from week to week and from day to day in individual patients. With rate exceptions there was no relationship between plasma methadone level and symptom complaints or between weekly chamges in plasma methadone level and changes in symptom complaints. Except possible to identify the ocassional patient with unusually low plasam methadone levels, the determination of methadone levels is not likely to be or practical value in methadone programs.

Facilitated uptake of a bioactive metabolite of maritime pine bark extract (pycnogenol into human erythrocytes.

Directory of Open Access Journals (Sweden)

Max Kurlbaum

Full Text Available Many plant secondary metabolites exhibit some degree of biological activity in humans. It is a common observation that individual plant-derived compounds in vivo are present in the nanomolar concentration range at which they usually fail to display measurable activity in vitro. While it is debatable that compounds detected in plasma are not the key effectors of bioactivity, an alternative hypothesis may take into consideration that measurable concentrations also reside in compartments other than plasma. We analysed the binding of constituents and the metabolite δ-(3,4-dihydroxy-phenyl-γ-valerolactone (M1, that had been previously detected in plasma samples of human consumers of pine bark extract Pycnogenol, to human erythrocytes. We found that caffeic acid, taxifolin, and ferulic acid passively bind to red blood cells, but only the bioactive metabolite M1 revealed pronounced accumulation. The partitioning of M1 into erythrocytes was significantly diminished at higher concentrations of M1 and in the presence of glucose, suggesting a facilitated transport of M1 via GLUT-1 transporter. This concept was further supported by structural similarities between the natural substrate α-D-glucose and the S-isomer of M1. After cellular uptake, M1 underwent further metabolism by conjugation with glutathione. We present strong indication for a transporter-mediated accumulation of a flavonoid metabolite in human erythrocytes and subsequent formation of a novel glutathione adduct. The physiologic role of the adduct remains to be elucidated.

The antimicrobial propeptide hCAP-18 plasma levels in neutropenia of various aetiologies

DEFF Research Database (Denmark)

Ye, Ying; Carlsson, Göran; Karlsson-Sjöberg, Jenny M T

2015-01-01

The underlying cause of neutropenia may be difficult to determine due to similar clinical presentation in many neutropenic conditions. The neutrophil protein hCAP-18 (pro-LL-37) is a major component of neutrophil secondary granules and in this prospective study we assessed the use of hCAP-18 levels...... in blood plasma for differential diagnosis of neutropenic patients (n = 133) of various aetiologies. Plasma levels of hCAP-18 were determined using immunoblot and ELISA. Patients with severe congenital neutropenia (n = 23) presented with the lowest levels of plasma hCAP-18 and differential diagnostic...... diagnostic value in differential diagnosis of chronic neutropenia. Neutropenic patients with Shwachman-Diamond syndrome, Barth syndrome, Cohen syndrome, acute myeloid leukaemia and specific granule deficiency presented with reduced plasma hCAP-18 levels as well. The blood plasma level of hCAP-18 was thus low...

Effects of in vivo irradiation on plasma levels of carotenoids and vitamin A

International Nuclear Information System (INIS)

White, W.S.; Roe, D.A.

1986-01-01

The aims of this investigation were to determine whether ultraviolet irradiation induces alterations in plasma carotenoid and vitamin A levels in human subjects. Twelve Caucasian women participated in an 8-week crossover trial. UV exposures were given to the anterior and posterior sides of the body on 11 days of a 2-week period. Mean cumulative UVA (320-400 nm) doses of 17.9 +/- 2.6 J/cm 2 and 24.1 +/- 1.5 J/cm 2 were delivered to the anterior and posterior sides, respectively. UVB (280-320 nm) doses were equivalent to 10% of the UVA doses given. Intake of carotenoids and preformed vitamin A was held constant. Plasma samples were collected weekly for spectrophotometric analysis of total carotenoids and vitamin A. A significant reduction (p < 0.003) in plasma carotenoid levels was observed following repeated irradiation. Although a significant treatment response could not be demonstrated for plasma vitamin A (p=0.11), a significant test for carryover (p < 0.02) suggested a delayed or continuing increase in plasma levels following irradiation. It is concluded that UV irradiation can reduce plasma carotenoid levels in vivo and may also affect plasma vitamin A levels in an adaptive response

Purification and H-1 NMR spectroscopic characterization of phase II metabolites of tolfenamic acid

DEFF Research Database (Denmark)

Sidelmann, U. G.; Christiansen, E.; Krogh, L.

1997-01-01

samples obtained on days 7 to 10 from a human volunteer after oral administration of 200 mg of the drug three times per day (steady-state plasma concentration). The metabolites of tolfenamic acid were initially concentrated by preparative solid phase extraction (PSPE) chromatography, thereby removing...... the endogenous polar compounds that are present in the urine. The individual metabolites were purified by preparative high performance liquid chromatography (HPLC) and then identified using H-1 NMR, Both one- and two-dimensional NMR experiments were performed to identify the phase II metabolites of tolfenamic......), and N-(2-methyl-4-hydroxyphenyl)-anthranilic acid (11) were identified. The phase II metabolites (5-11) had not previously been identified in urine from humans administered tolfenamic acid. The phase I metabolites of the glucuronides 7, 8, 10, and 11 were identified here for the first time. An HPLC...

Plasma neuropeptide Y levels differ in distinct diabetic conditions.

Science.gov (United States)

Ilhan, Aysegül; Rasul, Sazan; Dimitrov, Alexander; Handisurya, Ammon; Gartner, Wolfgang; Baumgartner-Parzer, Sabina; Wagner, Ludwig; Kautzky-Willer, Alexandra; Base, Wolfgang

2010-12-01

Neuropeptide Y (NPY) is an important hormone in appetite regulation. Although the contribution of NPY to metabolic disease has been previously demonstrated, there are only a few reports addressing NPY plasma levels under distinct diabetic conditions. In this study we evaluated NPY plasma levels in diabetes mellitus type 2 (DM2) patients with (n=34) and without (n=34) diabetic polyneuropathy (PNP) and compared these with age and gender matched healthy controls (n=34). We also analyzed NPY plasma levels in gestational diabetes mellitus (GDM) patients with age and pregnancy-week matched controls with normal glucose tolerance (NGT). NPY concentration was determined using a commercially available radioimmunoassay kit. In addition, metabolic parameters of DM2 and GDM patients were recorded. One-way ANOVA tests with appropriate post hoc corrections showed elevated levels of NPY in DM2 patients with and without PNP when compared with those of healthy controls (122.32±40.86 and 117.33±29.92 vs. 84.65±52.17 pmol/L; pwomen with NGT (74.87±14.36 vs. 84.82±51.13 pmol/L, respectively). Notably, the NPY concentration correlated positively with insulin levels in DM2 patients (R=0.35, pDM2 pathology. Copyright © 2010 Elsevier Ltd. All rights reserved.

Enzymatic sulfation of tocopherols and tocopherol metabolites by human cytosolic sulfotransferases.

Science.gov (United States)

Hashiguchi, Takuyu; Kurogi, Katsuhisa; Sakakibara, Yoichi; Yamasaki, Masao; Nishiyama, Kazuo; Yasuda, Shin; Liu, Ming-Cheh; Suiko, Masahito

2011-01-01

Tocopherols are essential micronutrients for mammals widely known as potent lipid-soluble antioxidants that are present in cell membranes. Recent studies have demonstrated that most of the carboxychromanol (CEHC), a tocopherol metabolite, in the plasma exists primarily in sulfate- and glucuronide-conjugated forms. To gain insight into the enzymatic sulfation of tocopherols and their metabolites, a systematic investigation was performed using all 14 known human cytosolic sulfotransferases (SULTs). The results showed that the members of the SULT1 family displayed stronger sulfating activities toward tocopherols and their metabolites. These enzymes showed a substrate preference for γ-tocopherol over α-tocopherol and for γ-CEHC over other CEHCs. Using A549 human lung epithelial cells in a metabolic labeling study, a similar trend in the sulfation of tocopherols and CEHCs was observed. Collectively, the results obtained indicate that SULT-mediated enzymatic sulfation of tocopherols and their metabolites is a significant pathway for regulation of the homeostasis and physiological functions of these important compounds.

Effect of experimental quinine administration on plasma levels of ...

African Journals Online (AJOL)

Six hours after the last dose administration, blood samples were withdrawn for the determination of plasma levels of hemoglobin and methemoglobin. Plasma hemoglobin concentration increased from 11.55 +0.32 g/100ml to a critical value of 14.30 g/100ml from the control to 0.08 g/kg dose administration. A further increase ...

Clinical significance of changes of plasma CGRP and VIP levels in infants with bronchiolitis

International Nuclear Information System (INIS)

Yang Chun; Gu Ling; Zhang Yanjun; Xin Haiyan

2005-01-01

Objective: To explore the clinical significance of changes of calcitonin gene-related peptide (CGRP) and vasoactive intestinal peptide (VIP) levels in infants (2-24months) with bronchiolitis. Methods: Plasma levels of CGRP and VIP were determined with RIA in 31 infants with bronchiolitis both during acute infection and convalescence as well as in 35 controls. Results: Plasma CGRP levels in patients during acute infection were significantly higher than those in patients during convalescence and in controls (P<0.05). Levels of CGRP dropped during convalescence, but still remained significantly higher than those in controls (P<0.05). The reverse was true for the plasma VIP levels. The plasma VIP levels in patients during acute infection were significantly lower than those in patients during convalescence and in controls (P<0.05). During convalescence, the plasma VIP levels rose but remained significantly lower than those in controls (P<0.05). Conclusion: There were dynamic changes of plasma CGRP and VIP levels in the course of infant bronchiolitis and the two peptides played opposite roles. (authors)

Metabolite Damage and Metabolite Damage Control in Plants

Energy Technology Data Exchange (ETDEWEB)

Hanson, Andrew D. [Horticultural Sciences Department and; Henry, Christopher S. [Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, Illinois 60439, email:; Computation Institute, University of Chicago, Chicago, Illinois 60637; Fiehn, Oliver [Genome Center, University of California, Davis, California 95616, email:; de Crécy-Lagard, Valérie [Microbiology and Cell Science Department, University of Florida, Gainesville, Florida 32611, email: ,

2016-04-29

It is increasingly clear that (a) many metabolites undergo spontaneous or enzyme-catalyzed side reactions in vivo, (b) the damaged metabolites formed by these reactions can be harmful, and (c) organisms have biochemical systems that limit the buildup of damaged metabolites. These damage-control systems either return a damaged molecule to its pristine state (metabolite repair) or convert harmful molecules to harmless ones (damage preemption). Because all organisms share a core set of metabolites that suffer the same chemical and enzymatic damage reactions, certain damage-control systems are widely conserved across the kingdoms of life. Relatively few damage reactions and damage-control systems are well known. Uncovering new damage reactions and identifying the corresponding damaged metabolites, damage-control genes, and enzymes demands a coordinated mix of chemistry, metabolomics, cheminformatics, biochemistry, and comparative genomics. This review illustrates the above points using examples from plants, which are at least as prone to metabolite damage as other organisms.

Estimation of placental and lactational transfer and tissue distribution of atrazine and its main metabolites in rodent dams, fetuses, and neonates with physiologically based pharmacokinetic modeling

International Nuclear Information System (INIS)

Lin, Zhoumeng; Fisher, Jeffrey W.; Wang, Ran; Ross, Matthew K.; Filipov, Nikolay M.

2013-01-01

Atrazine (ATR) is a widely used chlorotriazine herbicide, a ubiquitous environmental contaminant, and a potential developmental toxicant. To quantitatively evaluate placental/lactational transfer and fetal/neonatal tissue dosimetry of ATR and its major metabolites, physiologically based pharmacokinetic models were developed for rat dams, fetuses and neonates. These models were calibrated using pharmacokinetic data from rat dams repeatedly exposed (oral gavage; 5 mg/kg) to ATR followed by model evaluation against other available rat data. Model simulations corresponded well to the majority of available experimental data and suggest that: (1) the fetus is exposed to both ATR and its major metabolite didealkylatrazine (DACT) at levels similar to maternal plasma levels, (2) the neonate is exposed mostly to DACT at levels two-thirds lower than maternal plasma or fetal levels, while lactational exposure to ATR is minimal, and (3) gestational carryover of DACT greatly affects its neonatal dosimetry up until mid-lactation. To test the model's cross-species extrapolation capability, a pharmacokinetic study was conducted with pregnant C57BL/6 mice exposed (oral gavage; 5 mg/kg) to ATR from gestational day 12 to 18. By using mouse-specific parameters, the model predictions fitted well with the measured data, including placental ATR/DACT levels. However, fetal concentrations of DACT were overestimated by the model (10-fold). This overestimation suggests that only around 10% of the DACT that reaches the fetus is tissue-bound. These rodent models could be used in fetal/neonatal tissue dosimetry predictions to help design/interpret early life toxicity/pharmacokinetic studies with ATR and as a foundation for scaling to humans. - Highlights: • We developed PBPK models for atrazine in rat dams, fetuses, and neonates. • We conducted pharmacokinetic (PK) study with atrazine in pregnant mice. • Model predictions were in good agreement with experimental rat and mouse PK data. �

Estimation of placental and lactational transfer and tissue distribution of atrazine and its main metabolites in rodent dams, fetuses, and neonates with physiologically based pharmacokinetic modeling

Energy Technology Data Exchange (ETDEWEB)

Lin, Zhoumeng [Department of Physiology and Pharmacology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602 (United States); Interdisciplinary Toxicology Program, University of Georgia, Athens, GA 30602 (United States); Fisher, Jeffrey W. [Division of Biochemical Toxicology, National Center for Toxicological Research, Food and Drug Administration, Jefferson, AR 72079 (United States); Wang, Ran [Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762 (United States); Institute of Food Safety, Jiangsu Academy of Agricultural Sciences, Nanjing 210014 (China); Ross, Matthew K. [Center for Environmental Health Sciences, Department of Basic Sciences, College of Veterinary Medicine, Mississippi State University, Mississippi State, MS 39762 (United States); Filipov, Nikolay M., E-mail: filipov@uga.edu [Department of Physiology and Pharmacology, College of Veterinary Medicine, University of Georgia, Athens, GA 30602 (United States); Interdisciplinary Toxicology Program, University of Georgia, Athens, GA 30602 (United States)

2013-11-15

Atrazine (ATR) is a widely used chlorotriazine herbicide, a ubiquitous environmental contaminant, and a potential developmental toxicant. To quantitatively evaluate placental/lactational transfer and fetal/neonatal tissue dosimetry of ATR and its major metabolites, physiologically based pharmacokinetic models were developed for rat dams, fetuses and neonates. These models were calibrated using pharmacokinetic data from rat dams repeatedly exposed (oral gavage; 5 mg/kg) to ATR followed by model evaluation against other available rat data. Model simulations corresponded well to the majority of available experimental data and suggest that: (1) the fetus is exposed to both ATR and its major metabolite didealkylatrazine (DACT) at levels similar to maternal plasma levels, (2) the neonate is exposed mostly to DACT at levels two-thirds lower than maternal plasma or fetal levels, while lactational exposure to ATR is minimal, and (3) gestational carryover of DACT greatly affects its neonatal dosimetry up until mid-lactation. To test the model's cross-species extrapolation capability, a pharmacokinetic study was conducted with pregnant C57BL/6 mice exposed (oral gavage; 5 mg/kg) to ATR from gestational day 12 to 18. By using mouse-specific parameters, the model predictions fitted well with the measured data, including placental ATR/DACT levels. However, fetal concentrations of DACT were overestimated by the model (10-fold). This overestimation suggests that only around 10% of the DACT that reaches the fetus is tissue-bound. These rodent models could be used in fetal/neonatal tissue dosimetry predictions to help design/interpret early life toxicity/pharmacokinetic studies with ATR and as a foundation for scaling to humans. - Highlights: • We developed PBPK models for atrazine in rat dams, fetuses, and neonates. • We conducted pharmacokinetic (PK) study with atrazine in pregnant mice. • Model predictions were in good agreement with experimental rat and mouse PK data

Phenylalanine and tyrosine levels are rate-limiting factors in production of health promoting metabolites in Vitis vinifera cv. Gamay Red cell suspension.

Science.gov (United States)

Manela, Neta; Oliva, Moran; Ovadia, Rinat; Sikron-Persi, Noga; Ayenew, Biruk; Fait, Aaron; Galili, Gad; Perl, Avichai; Weiss, David; Oren-Shamir, Michal

2015-01-01

Environmental stresses such as high light intensity and temperature cause induction of the shikimate pathway, aromatic amino acids (AAA) pathways, and of pathways downstream from AAAs. The induction leads to production of specialized metabolites that protect the cells from oxidative damage. The regulation of the diverse AAA derived pathways is still not well understood. To gain insight on that regulation, we increased AAA production in red grape Vitis vinifera cv. Gamay Red cell suspension, without inducing external stress on the cells, and characterized the metabolic effect of this induction. Increased AAA production was achieved by expressing a feedback-insensitive bacterial form of 3-deoxy- D-arabino-heptulosonate 7-phosphate synthase enzyme (AroG (*)) of the shikimate pathway under a constitutive promoter. The presence of AroG(*) protein led to elevated levels of primary metabolites in the shikimate and AAA pathways including phenylalanine and tyrosine, and to a dramatic increase in phenylpropanoids. The AroG (*) transformed lines accumulated up to 20 and 150 fold higher levels of resveratrol and dihydroquercetin, respectively. Quercetin, formed from dihydroquercetin, and resveratrol, are health promoting metabolites that are induced due to environmental stresses. Testing the expression level of key genes along the stilbenoids, benzenoids, and phenylpropanoid pathways showed that transcription was not affected by AroG (*). This suggests that concentrations of AAAs, and of phenylalanine in particular, are rate-limiting in production of these metabolites. In contrast, increased phenylalanine production did not lead to elevated concentrations of anthocyanins, even though they are also phenylpropanoid metabolites. This suggests a control mechanism of this pathway that is independent of AAA concentration. Interestingly, total anthocyanin concentrations were slightly lower in AroG(*) cells, and the relative frequencies of the different anthocyanins changed as well.

Phenylalanine and tyrosine levels are rate-limiting factors in production of health promoting metabolites in Vitis vinifera cv. Gamay Red cell suspension

Directory of Open Access Journals (Sweden)

Neta eManela

2015-07-01

Full Text Available Environmental stresses such as high light intensity and temperature cause induction of the shikimate pathway, aromatic amino acids (AAA pathways, and of pathways downstream from AAAs. The induction leads to production of specialized metabolites that protect the cells from oxidative damage. The regulation of the diverse AAA derived pathways is still not well understood. To gain insight on that regulation, we increased AAA production in red grape Vitis vinifera cv. Gamay Red cell suspension, without inducing external stress on the cells, and characterized the metabolic effect of this induction. Increased AAA production was achieved by expressing a feedback-insensitive bacterial form of 3-deoxy- D-arabino-heptulosonate 7-phosphate synthase enzyme (AroG* of the shikimate pathway under a constitutive promoter. The presence of AroG* protein led to elevated levels of primary metabolites in the shikimate and AAA pathways including phenylalanine and tyrosine, and to a dramatic increase in phenylpropanoids. The AroG* transformed lines accumulated up to 20 and 150 fold higher levels of resveratrol and dihydroquercetin, respectively. Quercetin, formed from dihydroquercetin, and resveratrol, are health promoting metabolites that are induced due to environmental stresses. Testing the expression level of key genes along the stilbenoids, benzenoids and phenylpropanoid pathways showed that transcription was not affected by AroG*. This suggests that concentrations of AAAs, and of phenylalanine in particular, are rate-limiting in production of these metabolites. In contrast, increased phenylalanine production did not lead to elevated concentrations of anthocyanins, even though they are also phenylpropanoid metabolites. This suggests a control mechanism of this pathway that is independent of AAA concentration. Interestingly, total anthocyanin concentrations were slightly lower in AroG* cells, and the relative frequencies of the different anthocyanins changed as

Plasma Triglyceride and Cholesterol Levels in Normotensive and ...

African Journals Online (AJOL)

Plasma Triglyceride and Cholesterol Levels in Normotensive and Hypertensive Pregnant and Parturient Nigerian Women. Kashope D. Thomas, Oyebola G. Adeosun, Norah O. Akinola, Uche Onwudiegwu, Alexander T. Owolabi ...

Ozone effects on radish (Raphanus sativus L. cv. Cherry Belle): foliar sensitivity as related to metabolite levels and cell architecture

Energy Technology Data Exchange (ETDEWEB)

Athanassious, R.

1980-01-01

The development of the first four leaves of radish (Raphanus sativus L. cv. Cherry Belle) was followed to determine the relationship between foliar sensitivity to ozone as related to selected soluble metabolites and leaf-cell arrangement. Although relatively high metabolite (protein, sugars, phenols) levels and compact cell arrangement may be advanced as factors contributing to the resistance of young leaves (L/sub 3,4/ of 21-day old plants) these same parameters do not explain the resistance of old leaves (L/sub 1,2/ of 30-day old plants). 16 references, 4 figures, 1 table.

Metabolite Profiling of Red Sea Corals

KAUST Repository

Ortega, Jovhana Alejandra

2016-12-01

Looking at the metabolite profile of an organism provides insights into the metabolomic state of a cell and hence also into pathways employed. Little is known about the metabolites produced by corals and their algal symbionts. In particular, corals from the central Red Sea are understudied, but interesting study objects, as they live in one of the warmest and most saline environments and can provide clues as to the adjustment of corals to environmental change. In this study, we applied gas chromatography – mass spectrometry (GC–MS) metabolite profiling to analyze the metabolic profile of four coral species and their associated symbionts: Fungia granulosa, Acropora hemprichii, Porites lutea, and Pocillopora verrucosa. We identified and quantified 102 compounds among primary and secondary metabolites across all samples. F. granulosa and its symbiont showed a total of 59 metabolites which were similar to the 51 displayed by P. verrucosa. P. lutea and A. hemprichii both harbored 40 compounds in conjunction with their respective isolated algae. Comparing across species, 28 metabolites were exclusively present in algae, while 38 were exclusive to corals. A principal component and cluster analyses revealed that metabolite profiles clustered between corals and algae, but each species harbored a distinct catalog of metabolites. The major classes of compounds were carbohydrates and amino acids. Taken together, this study provides a first description of metabolites of Red Sea corals and their associated symbionts. As expected, the metabolites of coral hosts differ from their algal symbionts, but each host and algal species harbor a unique set of metabolites. This corroborates that host-symbiont species pairs display a fine-tuned complementary metabolism that provide insights into the specific nature of the symbiosis. Our analysis also revealed aquatic pollutants, which suggests that metabolite profiling might be used for monitoring pollution levels and assessing

Radioimmunoassay of Human Thyrotropin - Part 1. Plasma TSH levels in various thyroid functions

International Nuclear Information System (INIS)

Koh, Chang Soon; Lee, Hong Kyu; Ro, Heung Kyu; Lee, Mun Ho

1972-01-01

The radioimmunoassay of human thyrotropin was performed in various thyroid states, utilizing the anti-h-T.S.H. antibody and purified human thyrotropin supplied from National Institute of Arthritis and Metabolic Diseases, Bethesda, Ma., U.S.A., and human thyrotropin standard-A obtained from National Institute for Biologic Standards, Mill Hill, London, England. 131 I labelled h-TSH was prepared after the Chloramine-T method of Greenwood et al. This double antibody system had a assay sensitivity of about l. 0 μU/ml of plasma HTS-A and could detect the plasma h-TSH level in the euthyroid patients. Plasma h-TSH level of the normal 26 Korean was l.1±0. 83 μU/ml, and that of the 8 hypothyroidisms were 8.3 to 67.5 μU/ml. In hyperthyroidisms, no cases showed the plasma h-TSH levels over l. 0 μU/ ml. Between the hypothyroidism and euthyroidism, no overlap is noticed on plasma h-TSH levels. A case of transient hypothyroid state identified by determination of plasma h-TSH level is presented. These results revealed that the radioimmunoassay of h-TSH in plasma could be a sensitive method to diagnose the hypothyroidism, if not caused by a pituitary disease.

Plasma Antimicrobial Peptide LL-37 Level Is Inversely Associated with HDL Cholesterol Level in Patients with Type 2 Diabetes Mellitus

Directory of Open Access Journals (Sweden)

Shu Meguro

2014-01-01

Full Text Available Introduction. Relation between atherosclerosis and innate immunity has attracted attention. As the antimicrobial peptide, LL-37, could have an important role in atherosclerosis, we supposed that there could be a meaningful association of plasma LL-37 level with risk factors for cardiovascular disease in subjects with type 2 diabetes mellitus. Materials and Methods. We evaluated plasma LL-37 level and other clinical markers in Japanese subjects with type 2 diabetes mellitus (n=133, 115 men and 18 women; age 64.7±11.5 years; HbA1c 8.1±1.6%. Plasma level of LL-37 was measured by ELISA. Results. Mean plasma LL-37 level was 71.2±22.3 ng/mL. Plasma LL-37 level showed significant correlations with HDL cholesterol (r=−0.450, P<0.01, triglyceride (r=0.445, P<0.01, and high sensitive C-reactive protein (r=0.316, P<0.01 but no significant correlation with age, body mass index, HbA1c, estimated glomerular filtration rate, 25-hydroxyvitamin D, or vitamin D binding protein. Multiple linear regression analysis showed significant correlations of plasma LL-37 level with HDL cholesterol (β=−0.411, P<0.01 and high sensitive C-reactive protein (β=0.193, P<0.05. Conclusion. Plasma LL-37 level was positively correlated with inflammatory markers and negatively correlated with HDL cholesterol in patients with type 2 diabetes mellitus.

Quantitative determination of regorafenib and its two major metabolites in human plasma with high-performance liquid chromatography and ultraviolet detection.

Science.gov (United States)

Fujita, Kazuma; Miura, Masatomo; Shibata, Hiroyuki

2016-10-01

A simple, highly sensitive and specific high-performance liquid chromatography (HPLC) method was developed for the simultaneous quantitation of regorafenib, N-oxidemetabolite (M-2) and the desmethyl N-oxide metabolite (M-5) in human plasma. Regorafenib, M-2, M-5 and the internal standard sorafenib were separated using a mobile phase of 0.5% KH2 PO4 (pH 3.5)-acetonitrile (30:70, v/v), on a Capcell PAK MG II column at a flow rate of 0.5 mL/min and measurement at UV 260 nm. The lower limits of quantification for regorafenib, M-2 and M-5 were 10 ng/mL for each analyte. A procedure using solid-phase extraction required only a small amount of plasma (100 μL) for one analysis while providing high extraction recovery (>81% for all compounds) and good selectivity. Coefficients of variation for intra- and inter-day assays were HPLC assay is suitable for clinical pharmacokinetic studies of regorafenib. The present HPLC method is currently in use for our observational studies of patients under treatment. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

Phthalate metabolites in the European eel (Anguilla anguilla) from Mediterranean coastal lagoons.

Science.gov (United States)

Fourgous, C; Chevreuil, M; Alliot, F; Amilhat, E; Faliex, E; Paris-Palacios, S; Teil, M J; Goutte, A

2016-11-01

The levels and fate of phthalate metabolites have been poorly evaluated in fish, despite their potential ecotoxicological impacts. The present study aims to characterize the levels of phthalate metabolites in muscle tissue of yellow eels (Anguilla anguilla) from two coastal Mediterranean lagoons, during three sampling periods. Nine phthalate metabolites were detected in >70% of the samples. Slightly higher levels of phthalate metabolites were detected in March and June compared to October, suggesting possible seasonal variations in environmental release and/or phthalate metabolization process by eels. The large sample size (N=117) made it possible to explore correlations between phthalate metabolites' levels and individual parameters, such as body length, age, body condition and hepatic histo-pathologies. Body length and estimated age poorly correlated with phthalate metabolites, suggesting that eels did not accumulate phthalates during growth, contrary to persistent compounds. Eels presented different grades of hepatic fibrosis and lipidosis. A negative correlation was found between the severity of these pathologies in the liver and the sum of phthalate metabolites levels, supporting the hypothesis that eels with damaged liver are less able to metabolize xenobiotics. Copyright © 2016 Elsevier B.V. All rights reserved.

Impairment of memory and plasma flunitrazepam levels

NARCIS (Netherlands)

Bareggi, [No Value; Ferini-Strambi, L; Pirola, R; Smirne, S

Flunitrazepam was administered to volunteers in three different oral doses. The effects on psychomotor sedation, attention, working memory and explicit memory were then assessed at various intervals after dosing and compared with levels of the drug in the plasma. Three groups of 12 healthy males

Impairment of memory and plasma flunitrazepam levels

NARCIS (Netherlands)

Bareggi, [No Value; Ferini-Strambi, L; Pirola, R; Smirne, S

1998-01-01

Flunitrazepam was administered to volunteers in three different oral doses. The effects on psychomotor sedation, attention, working memory and explicit memory were then assessed at various intervals after dosing and compared with levels of the drug in the plasma. Three groups of 12 healthy males

Relationship between Plasma Leptin Level and Chronic Kidney Disease

Directory of Open Access Journals (Sweden)

Anoop Shankar

2012-01-01

Full Text Available Background. Leptin is an adipose tissue-derived hormone shown to be related to several metabolic, inflammatory, and hemostatic factors related to chronic kidney disease. Recent animal studies have reported that infusion of recombinant leptin into normal rats for 3 weeks fosters the development of glomerulosclerosis. However, few studies have examined the association between leptin and CKD in humans. Therefore, we examined the association between plasma leptin levels and CKD in a representative sample of US adults. Methods. We examined the third National Health and Nutrition Examination Survey participants >20 years of age (n=5820, 53.6% women. Plasma leptin levels were categorized into quartiles (≤4.3 Fg/L, 4.4–8.7 Fg/L, 8.8–16.9 Fg/L, >16.9 Fg/L. CKD was defined as a glomerular filtration rate of <60 mL/min/1.73 m2 estimated from serum creatinine. Results. Higher plasma leptin levels were associated with CKD after adjusting for age, sex, race/ethnicity, education, smoking, alcohol intake, body mass index (BMI, diabetes, hypertension, and serum cholesterol. Compared to quartile 1 of leptin (referent, the odds ratio (95% confidence interval of CKD associated with quartile 4 was 3.31 (1.41 to 7.78; P-trend = 0.0135. Subgroup analyses examining the relation between leptin and CKD by gender, BMI categories, diabetes, and hypertension status also showed a consistent positive association. Conclusion. Higher plasma leptin levels are associated with CKD in a representative sample of US adults.

Development and validation of a high performance liquid chromatography quantification method of levo-tetrahydropalmatine and its metabolites in plasma and brain tissues: application to a pharmacokinetic study.

Science.gov (United States)

Abdallah, Inas A; Huang, Peng; Liu, Jing; Lee, David Y; Liu-Chen, Lee-Yuan; Hassan, Hazem E

2017-04-01

Levo-tetrahydropalmatine (l-THP) is an alkaloid isolated from Chinese medicinal herbs of the Corydalis and Stephania genera. It has been used in China for more than 40 years mainly as an analgesic with sedative/hypnotic effects. Despite its extensive use, its metabolism has not been quantitatively studied, nor there a sensitive reliable bioanalytical method for its quantification simultaneously with its metabolites. As such, the objective of this study was to develop and validate a sensitive and selective HPLC method for simultaneous quantification of l-THP and its desmethyl metabolites l-corydalmine (l-CD) and l-corypalmine (l-CP) in rat plasma and brain tissues. Rat plasma and brain samples were processed by liquid-liquid extraction using ethyl acetate. Chromatographic separation was achieved on a reversed-phase Symmetry® C 18 column (4.6 × 150 mm, 5 μm) at 25°C. The mobile phase consisted of acetonitrile-methanol-10 mm ammonium phosphate (pH 3) (10:30:60, v/v) and was used at a flow rate of 0.8 mL/min. The column eluent was monitored at excitation and emission wavelengths of 230 and 315 nm, respectively. The calibration curves were linear over the concentration range of 1-10,000 ng/mL. The intra- and interday reproducibility studies demonstrated accuracy and precision within the acceptance criteria of bioanalytical guidelines. The validated HPLC method was successfully applied to analyze samples from a pharmacokinetic study of l-THP in rats. Taken together, the developed method can be applied for bioanalysis of l-THP and its metabolites in rodents and potentially can be transferred for bioanalysis of human samples. Copyright © 2016 John Wiley & Sons, Ltd.

Physical activity opposes the age-related increase in skeletal muscle and plasma endothelin-1 levels and normalizes plasma endothelin-1 levels in individuals with essential hypertension

DEFF Research Database (Denmark)

Nyberg, Michael Permin; Mortensen, Stefan Peter; Hellsten, Ylva

2013-01-01

performed lifelong physical activity had similar plasma and muscle endothelin-1 levels as the young controls and had higher ET(A) receptor levels. CONCLUSION: Our findings suggest that aerobic exercise training opposes the age-related increase in skeletal muscle and plasma endothelin-1 levels and normalizes......AIMS: Endothelin-1 has potent constrictor and proliferative activity in vascular smooth muscle, and essential hypertension and aging are associated with increased endothelin-1-mediated vasoconstrictor tone. The aim of this study was to investigate the effect of physical activity, hypertension...... and age on endothelin-1 levels in plasma and skeletal muscle and endothelin receptors in skeletal muscle in human subjects. METHODS: In study 1, normotensive (46 ± 1 years, n = 11) and hypertensive (47 ± 1 years, n = 10) subjects were studied before and after 8 weeks of aerobic exercise training. In study...

Variability in urinary phthalate metabolite levels across pregnancy and sensitive windows of exposure for the risk of preterm birth

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Ferguson, Kelly K.; McElrath, Thomas F.; Ko, Yi-An; Mukherjee, Bhramar; Meeker, John D.

2014-01-01

Background Preterm birth is a significant public health problem, affecting over 1 in 10 live births and contributing largely to infant mortality and morbidity. Everyday exposure to environmental chemicals such as phthalates could contribute, and may be modifiable. In the present study we examine variability in phthalate exposure across gestation and identify windows of susceptibility for the relationship with preterm birth. Methods Women were recruited early in pregnancy as part of a prospective, longitudinal birth cohort at the Brigham and Women’s Hospital in Boston, Massachusetts. Urine samples were collected at up to 4 time points during gestation for phthalate measurement, and birth outcomes were recorded at delivery. From this population we selected all 130 cases of preterm birth, defined as delivery before 37 weeks completed gestation, as well as 352 random controls. Results Urinary phthalate metabolite levels were moderately variable over pregnancy, but levels measured at multiple time points were associated with increased odds of preterm birth. Adjusted odds ratios (aOR) for spontaneous preterm birth were strongest in association with phthalate metabolite concentrations measured at the beginning of the third trimester (aOR for summed di-2-ethylhexyl phthalate metabolites [∑DEHP]=1.33, 95% confidence interval [CI]=1.02, 1.73). Odds ratios for placental preterm birth, defined as delivery with presentation of preeclampsia or intrauterine growth restriction, were slightly elevated in the first trimester for DEHP metabolites (aOR for ∑DEHP=1.33, 95% CI=0.99, 1.78). Conclusions Pregnant women with exposure to phthalates both early and late in pregnancy are at increased risk of delivering preterm, but mechanisms may differ based on etiology. PMID:24934852

Modulation of plasma fibrinogen levels by ciprofibrate and gemfibrozil in primary hyperlipidaemia

NARCIS (Netherlands)

de Maat, M. P.; Knipscheer, H. C.; Kastelein, J. J.; Kluft, C.

1997-01-01

An elevated plasma fibrinogen level is increasingly accepted as an independent risk indicator of cardiovascular disease. This has enhanced the interest in identifying agents that can normalize elevated plasma fibrinogen levels. One group of agents with this capacity are the fibric acid derivatives,

Regulatory metabolites of vitamin E and their putative relevance for atherogenesis

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Maria Wallert

2014-01-01

Full Text Available Vitamin E is likely the most important antioxidant in the human diet and α-tocopherol is the most active isomer. α-Tocopherol exhibits anti-oxidative capacity in vitro, and inhibits oxidation of LDL. Beside this, α-tocopherol shows anti-inflammatory activity and modulates expression of proteins involved in uptake, transport and degradation of tocopherols, as well as the uptake, storage and export of lipids such as cholesterol. Despite promising anti-atherogenic features in vitro, vitamin E failed to be atheroprotective in clinical trials in humans. Recent studies highlight the importance of long-chain metabolites of α-tocopherol, which are formed as catabolic intermediate products in the liver and occur in human plasma. These metabolites modulate inflammatory processes and macrophage foam cell formation via mechanisms different than that of their metabolic precursor α-tocopherol and at lower concentrations. Here we summarize the controversial role of vitamin E as a preventive agent against atherosclerosis and point the attention to recent findings that highlight a role of these long-chain metabolites of vitamin E as a proposed new class of regulatory metabolites. We speculate that the metabolites contribute to physiological as well as pathophysiological processes.

A Taiwanese food frequency questionnaire correlates with plasma docosahexaenoic acid but not with plasma eicosapentaenoic acid levels: questionnaires and plasma biomarkers.

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Chien, Kuo-Liong; Lee, Meei-Shyuan; Tsai, Yi-Tsen; Chen, Pey-Rong; Lin, Hung-Ju; Hsu, Hsiu-Ching; Lee, Yuan-The; Chen, Ming-Fong

2013-02-16

Little evidence is available for the validity of dietary fish and polyunsaturated fatty acid intake derived from interviewer-administered questionnaires and plasma docosahexaenoic acid (DHA) and eicosapentaenoic acid (EPA) concentration. We estimated the correlation of DHA and EPA intake from both questionnaires and biochemical measurements. Ethnic Chinese adults with a mean (± SD) age of 59.8 (±12.8) years (n = 297) (47% women) who completed a 38-item semi-quantitative food-frequency questionnaire and provided a plasma sample were enrolled. Plasma fatty acids were analyzed by capillary gas chromatography. The Spearmen rank correlation coefficients between the intake of various types of fish and marine n-3 fatty acids as well as plasma DHA were significant, ranging from 0.20 to 0.33 (P food frequency questionnaire, were correlated with the percentages of these fatty acids in plasma, and in particular with plasma DHA. Plasma DHA levels were correlated to dietary intake of long-chain n-3 fatty acids.

Plasma levels of cortisol and opioid peptide beta-endorphin during spontaneous vaginal delivery

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Arsenijević Ljubica

2006-01-01

Full Text Available INTRODUCTION Labor pain is very frequent in clinical practice, but the underlying mechanisms as well as numerous neuroendocrine responses activated by such pain have not been fully explained yet. OBJECTIVE The objective of the study was to determine the influence of labor pain on plasma levels of cortisol and opioid peptide ß-endorphin. METHOD Cortisol and ß-endorphin levels were measured in blood plasma of: health, non-pregnant women (group 1, n=8, health pregnant women (group 2, n=8 and in parturitions, through fourth ages (group 3, n=8, Plasma level of cortisol was measured by radioimmunoassay, and ß-endorphin by enzyme immunoassay. Data were expressed as mean ± standard error of mean and were analyzed by Student's t test and Mann Whitney test. RESULTS Plasma level of cortisol in group 2 was significantly increased compared to the group 1. During labor progression, plasma level of cortisol was rising till the third labor age. Plasma level of cortisol in fourth labor age was not significantly different from the ag.e one and group 1. Plasma level of ß-endorphin was (n.g/L: in group 1:64±20, group 2:70±22, group 3:the first labor age: 75±15, the second labor age: 193±54, the third labor age: 346+97 and the fourth labor age: 114±31. CONCLUSION These results indicate that both ß-endorphin and cortisol are involved in regulation and modulation of labor pain and stress.

Simultaneous Determination of 6-Mercaptopurine and its Oxidative Metabolites in Synthetic Solutions and Human Plasma using Spectrophotometric Multivariate Calibration Methods

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Mohammad-Reza Rashidi

2011-06-01

Full Text Available Introduction: 6-Mercaptopurine (6MP is an important chemotherapeutic drug in the conventional treatment of childhood acute lymphoblastic leukemia (ALL. It is catabolized to 6-thiouric acid (6TUA through 8-hydroxo-6-mercaptopurine (8OH6MP or 6-thioxanthine (6TX intermediates. Methods: High-performance liquid chromatography (HPLC is usually used to determine the contents of therapeutic drugs, metabolites and other important biomedical analytes in biological samples. In the present study, the multivariate calibration methods, partial least squares (PLS-1 and principle component regression (PCR have been developed and validated for the simultaneous determination of 6MP and its oxidative metabolites (6TUA, 8OH6MP and 6TX without analyte separation in spiked human plasma. Mixtures of 6MP, 8-8OH6MP, 6TX and 6TUA have been resolved by PLS-1 and PCR to their UV spectra. Results: Recoveries (% obtained for 6MP, 8-8OH6MP, 6TX and 6TUA were 94.5-97.5, 96.6-103.3, 95.1-96.9 and 93.4-95.8, respectively, using PLS-1 and 96.7-101.3, 96.2-98.8, 95.8-103.3 and 94.3-106.1, respectively, using PCR. The NAS (Net analyte signal concept was used to calculate multivariate analytical figures of merit such as limit of detection (LOD, selectivity and sensitivity. The limit of detections for 6MP, 8-8OH6MP, 6TX and 6TUA were calculated to be 0.734, 0.439, 0.797 and 0.482 µmol L-1, respectively, using PLS and 0.724, 0.418, 0783 and 0.535 µmol L-1, respectively, using PCR. HPLC was also applied as a validation method for simultaneous determination of these thiopurines in the synthetic solutions and human plasma. Conclusion: Combination of spectroscopic techniques and chemometric methods (PLS and PCR has provided a simple but powerful method for simultaneous analysis of multicomponent mixtures.

Plasma. beta. -endorphin and stress hormone levels during adaptation and stress

Energy Technology Data Exchange (ETDEWEB)

Lishmanov, Yu.B.; Trifonova, Zh.V.; Tsibin, A.N.; Maslova, L.V.; Dement' eva, L.A.

1987-09-01

This paper describes a comparative study of ..beta..-endorphin and stress hormone levels in the blood plasma of rats during stress and adaptation. Immunoreactive ..beta..-endorphin in the blood plasma was assayed by means of a kit after preliminary isolation of the ..beta..-endorphin fraction by affinity chromatography on sepharose; ACTH was assayed with a kit and cortisol, insulin, thyroxine and tri-iodothyronine by means of kits from Izotop. Determination of plasma levels of ..beta..-endorphin and other opioids could evidently be an important method of assessing the state of resistance of the organism to stress.

[Polycyclic aromatic hydrocarbons monohydroxy metabolites level in urine of general population in eight provinces of China].

Science.gov (United States)

Huang, Chuanfeng; Zhang, Jing; Ding, Chunguang; Liu, Cuilan; Wang, Gang; Song, Xinkui; Huang, Hanlin; Zhu, Baoli; Shao, Hua; Zhao, Chunxiang; Han, Changcheng; Peng, Shanzhuo; Jiang, Xianlong; Yu, Shanfa; Ji, Hongrong; Zhang, Xiaoxi; Sun, Ran; Zheng, Yuxin; Yan, Huifang

2014-02-01

To assess the levels of polycyclic aromatic hydrocarbons monohydroxy metabolites in urine of general population in China among 8 provinces, provide the baseline of the metabolites in the general population. From 2009 to 2010, 18 120 subjects of general population aged 6-60 years old were recruited from 24 areas among 8 provinces in east, west and central areas of China mainland by cluster random sampling. The information of the living environment and health condition were collected by questionnaire and spot urine samples were collected, 4 680 urine samples were analysed by high performance liquid chromatography with tandem mass spectrometry, and monohydroxy metabolites distribution in urine among groups of gender and ages were analysed. Geometric means (GM) of 2-naphthol, 1-naphthol, 3-phenanthrol and 1-hydroxypyrene concentration in urine (95%CI) were 1.85 (1.75-1.95), 1.55 (1.50-1.61), 0.57 (0.54-0.59) and 0.82 (0.78-0.85) µg/L, respectively;and median are 2.44, population were significantly different (P population aged 6-12, 13-16, 17-20, 21-30, 31-45 and 46-60 years old were 1.60, 1.56, 1.69, 2.23, 1.91 and 1.86 µg/L (χ(2) = 17.90, P population were different, it provided a basic data for the further study of polycyclic aromatic hydrocarbons biomonitoring in the population.

Development and Validation of a UPLC-MS/MS and UPLC-HR-MS Method for the Determination of Fumonisin B1 and Its Hydrolysed Metabolites and Fumonisin B2 in Broiler Chicken Plasma

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Siegrid De Baere

2018-01-01

Full Text Available A sensitive and specific method for the quantitative determination of Fumonisin B1 (FB1, its partially hydrolysed metabolites pHFB1a+b and hydrolysed metabolite HFB1, and Fumonisin B2 (FB2 in broiler chicken plasma using ultra-performance liquid chromatography combined with tandem mass spectrometry (UPLC-MS/MS was developed. The sample preparation was rapid, straightforward and consisted of a deproteinization and phospholipid removal step using an Oasis® OstroTM 96-well plate. Chromatography was performed on an Acquity HSS-T3 column, using 0.3% formic acid and 10 mM ammonium formate in water, and acetonitrile as mobile phases. The MS/MS instrument was operated in the positive electrospray ionization mode and the two multiple reaction monitoring transitions were monitored for each component for quantification and identification, respectively. The method was validated in-house: matrix-matched calibration graphs were prepared and good linearity (r ≥ 0.99 was achieved over the concentration ranges tested (1–500 ng/mL for FB1 and FB2; 0.86–860 ng/mL for pHFB1a; 0.72–1430 ng/mL for pHFB1b and 2.5–2500 ng/mL for HFB1. Limits of quantification (LOQ and detection (LOD in plasma ranged between 0.72 to 2.5 ng/mL and 0.03 to 0.17 ng/mL, respectively. The results for the within-day and between-day precision and accuracy fell within the specified ranges. Moreover, the method was transferred to an UPLC high-resolution mass spectrometry (HR-MS instrument in order to determine potential metabolites of HFB1, such as N-acyl-HFB1s and phase II metabolites. The method has been successfully applied to investigate the toxicokinetics and biotransformation of HFB1 in broiler chickens.

Impact of Cytochrome P450 2D6 Function on the Chiral Blood Plasma Pharmacokinetics of 3,4-Methylenedioxymethamphetamine (MDMA) and Its Phase I and II Metabolites in Humans.

Science.gov (United States)

Steuer, Andrea E; Schmidhauser, Corina; Tingelhoff, Eva H; Schmid, Yasmin; Rickli, Anna; Kraemer, Thomas; Liechti, Matthias E

2016-01-01

3,4-methylenedioxymethamphetamine (MDMA; ecstasy) metabolism is known to be stereoselective, with preference for S-stereoisomers. Its major metabolic step involves CYP2D6-catalyzed demethylenation to 3,4-dihydroxymethamphetamine (DHMA), followed by methylation and conjugation. Alterations in CYP2D6 genotype and/or phenotype have been associated with higher toxicity. Therefore, the impact of CYP2D6 function on the plasma pharmacokinetics of MDMA and its phase I and II metabolites was tested by comparing extensive metabolizers (EMs), intermediate metabolizers (IMs), and EMs that were pretreated with bupropion as a metabolic inhibitor in a controlled MDMA administration study. Blood plasma samples were collected from 16 healthy participants (13 EMs and three IMs) up to 24 h after MDMA administration in a double-blind, placebo-controlled, four-period, cross-over design, with subjects receiving 1 week placebo or bupropion pretreatment followed by a single placebo or MDMA (125 mg) dose. Bupropion pretreatment increased the maximum plasma concentration (Cmax) and area under the plasma concentration-time curve from 0 to 24 h (AUC24) of R-MDMA (9% and 25%, respectively) and S-MDMA (16% and 38%, respectively). Bupropion reduced the Cmax and AUC24 of the CYP2D6-dependently formed metabolite stereoisomers of DHMA 3-sulfate, DHMA 4-sulfate, and 4-hydroxy-3-methoxymethamphetamine (HMMA sulfate and HMMA glucuronide) by approximately 40%. The changes that were observed in IMs were generally comparable to bupropion-pretreated EMs. Although changes in stereoselectivity based on CYP2D6 activity were observed, these likely have low clinical relevance. Bupropion and hydroxybupropion stereoisomer pharmacokinetics were unaltered by MDMA co-administration. The present data might aid further interpretations of toxicity based on CYP2D6-dependent MDMA metabolism.

Impact of Cytochrome P450 2D6 Function on the Chiral Blood Plasma Pharmacokinetics of 3,4-Methylenedioxymethamphetamine (MDMA and Its Phase I and II Metabolites in Humans.

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Andrea E Steuer

Full Text Available 3,4-methylenedioxymethamphetamine (MDMA; ecstasy metabolism is known to be stereoselective, with preference for S-stereoisomers. Its major metabolic step involves CYP2D6-catalyzed demethylenation to 3,4-dihydroxymethamphetamine (DHMA, followed by methylation and conjugation. Alterations in CYP2D6 genotype and/or phenotype have been associated with higher toxicity. Therefore, the impact of CYP2D6 function on the plasma pharmacokinetics of MDMA and its phase I and II metabolites was tested by comparing extensive metabolizers (EMs, intermediate metabolizers (IMs, and EMs that were pretreated with bupropion as a metabolic inhibitor in a controlled MDMA administration study. Blood plasma samples were collected from 16 healthy participants (13 EMs and three IMs up to 24 h after MDMA administration in a double-blind, placebo-controlled, four-period, cross-over design, with subjects receiving 1 week placebo or bupropion pretreatment followed by a single placebo or MDMA (125 mg dose. Bupropion pretreatment increased the maximum plasma concentration (Cmax and area under the plasma concentration-time curve from 0 to 24 h (AUC24 of R-MDMA (9% and 25%, respectively and S-MDMA (16% and 38%, respectively. Bupropion reduced the Cmax and AUC24 of the CYP2D6-dependently formed metabolite stereoisomers of DHMA 3-sulfate, DHMA 4-sulfate, and 4-hydroxy-3-methoxymethamphetamine (HMMA sulfate and HMMA glucuronide by approximately 40%. The changes that were observed in IMs were generally comparable to bupropion-pretreated EMs. Although changes in stereoselectivity based on CYP2D6 activity were observed, these likely have low clinical relevance. Bupropion and hydroxybupropion stereoisomer pharmacokinetics were unaltered by MDMA co-administration. The present data might aid further interpretations of toxicity based on CYP2D6-dependent MDMA metabolism.

Comparative metabolomics in vegans and omnivores reveal constraints on diet-dependent gut microbiota metabolite production

Science.gov (United States)

Wu, Gary D; Compher, Charlene; Chen, Eric Z; Smith, Sarah A; Shah, Rachana D; Bittinger, Kyle; Chehoud, Christel; Albenberg, Lindsey G; Nessel, Lisa; Gilroy, Erin; Star, Julie; Weljie, Aalim M; Flint, Harry J; Metz, David C; Bennett, Michael J; Li, Hongzhe; Bushman, Frederic D; Lewis, James D

2015-01-01

Objective The consumption of an agrarian diet is associated with a reduced risk for many diseases associated with a ‘Westernised’ lifestyle. Studies suggest that diet affects the gut microbiota, which subsequently influences the metabolome, thereby connecting diet, microbiota and health. However, the degree to which diet influences the composition of the gut microbiota is controversial. Murine models and studies comparing the gut microbiota in humans residing in agrarian versus Western societies suggest that the influence is large. To separate global environmental influences from dietary influences, we characterised the gut microbiota and the host metabolome of individuals consuming an agrarian diet in Western society. Design and results Using 16S rRNA-tagged sequencing as well as plasma and urinary metabolomic platforms, we compared measures of dietary intake, gut microbiota composition and the plasma metabolome between healthy human vegans and omnivores, sampled in an urban USA environment. Plasma metabolome of vegans differed markedly from omnivores but the gut microbiota was surprisingly similar. Unlike prior studies of individuals living in agrarian societies, higher consumption of fermentable substrate in vegans was not associated with higher levels of faecal short chain fatty acids, a finding confirmed in a 10-day controlled feeding experiment. Similarly, the proportion of vegans capable of producing equol, a soy-based gut microbiota metabolite, was less than that was reported in Asian societies despite the high consumption of soy-based products. Conclusions Evidently, residence in globally distinct societies helps determine the composition of the gut microbiota that, in turn, influences the production of diet-dependent gut microbial metabolites. PMID:25431456