Pierre Marquet

French Institute of Health and Medical Research, Lutetia Parisorum, Île-de-France, France

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Publications (239)701.69 Total impact

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    ABSTRACT: Although therapeutic drug monitoring has improved the clinical use of immunosuppressive drugs, there is still interpatient variability in efficacy and toxicity that pharmacodynamic monitoring may help to reduce. To select the best biomarkers of tacrolimus pharmacodynamics, we explored the strength and variability of signal transduction and the influence of polymorphisms along the calcineurin pathway.
    Clinical chemistry. 08/2014;
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    ABSTRACT: A time to event model was developed to study predictive factors of immunosuppressive efficacy in renal transplant patients and to investigate longitudinal calcineurin inhibitors (CNIs) and mycophenolic acid (MPA) co-exposures, and patient characteristics as potential covariates. The efficacy endpoint included acute rejection, graft loss and death.Data from 222 patients were analyzed: 23 events were observed in 126 patients receiving cyclosporine against 15 in 96 patients receiving tacrolimus (p=0.61) in the two first years post-transplantation. Each 1mg.h/L increase of MPA AUC was associated with a 4% decreased risk of event (hazard ratio (HR) 95% confidence interval (CI): 0.93-0.99). The onset of cytomegalovirus infection/disease significantly increased this risk (HR=10.9; 95% CI: 6.5-21.7). Within the observed ranges, CNIs exposures were not significantly associated with efficacy (i.e. acute rejection, graft loss and death). This work advocates for the avoidance of unnecessary high CNIs dosing and puts forward new arguments for MPA concentration monitoring.Clinical Pharmacology & Therapeutics (2014); Accepted article preview online 26 June 2014; doi:10.1038/clpt.2014.140.
    Clinical pharmacology and therapeutics. 06/2014;
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    ABSTRACT: Purpose The aims of the present study were (1) to investigate the impact of great age on pharmacokinetics of capecitabine and its metabolites and (2) to evaluate the exposure–effect relationship of capecitabine in elderly patients. Methods Data collected from 20 elderly patients (75–92 years old) with breast or colorectal cancer who received oral capecitabine were analyzed. In order to study the old age effect on pharmacokinetics, data collected from two phase I studies involving 40 younger adults (<75 years old) with metastatic cancer who received oral capecitabine were added in the database. The population pharmacokinetic analysis was based on a four-compartment model describing the sequence of capecitabine and three of its metabolites. Results The absorption rate constant was found lower in the oldest patient group (≥75 years) compared with the youngest group, and the constant rate elimination of the 5-fluorouracil metabolite was found decreased over time (i.e., after 2 consecutive weeks of capecitabine administration). This time effect was not found different between the two age groups. In elderly patients, the exposure-safety analysis showed, from the second cycle of chemotherapy, significantly higher median exposures of capecitabine and its metabolites (5′-deoxy-5-fluorocytidine, 5′-deoxy-5-fluorouridine and 5-fluorouracil) in patients who experienced hand-foot syndrome compared with patients who did not. Conclusion This study puts forward new arguments for the treatment of elderly cancer patients who could benefit from capecitabine chemotherapy with acceptable toxicity.
    Cancer Chemotherapy and Pharmacology 06/2014; 73(6). · 2.80 Impact Factor
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    ABSTRACT: To describe the feasibility of human uterus retrieval after donation after brain death.
    Fertility and sterility. 05/2014;
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    ABSTRACT: AimsCyclosporine A (CsA) is used in the prophylaxis and treatment of acute and chronic graft-versus-host disease after hematopoietic stem cell (HCT) transplantation. Our objective were to build and compare three independent Bayesian estimators (BE) of CsA area under the curve (AUC) using a limited sampling strategy (LSS), to assist in dose adjustment.Methods The BEs were developed using in parallel: two independent parametric modeling approaches (NONMEM® and iterative two stage (ITS) Bayesian modeling) and the nonparametric adaptive grid method (Pmetrics®). Seventy-two full pharmacokinetic profiles (at pre-dose and 0.33, 0.66, 1, 2, 3, 4, 6, 8 and 12h after dosing) collected from 40 HCT patients given CsA were used to build the pharmacokinetic models, while 15 other profiles (n=7) were kept for validation. For each BE, AUCs estimated using the full profiles were compared to AUCs estimated using 3 samples.ResultsThe pharmacokinetic profiles were well fitted using a two-compartment model with first-order elimination, combined with a gamma function for the absorption phase with ITS and Pmetrics or an Erlang distribution with NONMEM. The derived BE based on a C0-C1h-C4h sampling schedule (best LSS) accurately estimated CsA AUC0-12h in the validation group (n=15; NONMEM: bias (mean ± SD)/RMSE=2.05%±13.31%/13.02%; ITS: 4.61%±10.56%/11.20%; Pmetrics: 0.30%±10.12%/10.47%). The dose chosen confronting the 3 results led to a pertinent dose proposal.ConclusionsBEs developed were all able to predict cyclosporine AUC0-12h in HCT patients using only three blood with minimal bias and may be combined to increase the reliability of CsA dose adjustment in routine.
    British Journal of Clinical Pharmacology 04/2014; · 3.69 Impact Factor
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    ABSTRACT: AimsThe use of mycophenolate mofetil (MMF) in children with Systemic Lupus Erythematosus (SLE) is increasing. However, the clinical benefit of its monitoring has been scarcely studied, and little is known about its pharmacokinetics in this context. The objectives of the present study were: (i) to describe mycophenolic acid (MPA; the active moiety of MMF) pharmacokinetics; (ii) to develop a Bayesian estimator (BE) allowing the determination AUC (Area under the curve) from a limited number of blood samples; and (ii) to explore the relationships between exposure indices to MPA and the clinical status in children with SLE.Methods This was a retrospective study including 36 children with SLE, extracted from the expert system ISBA, for whom full- pharmacokinetic profiles of MPA were collected together with clinical data. A pharmacokinetic model and a BE were developed using an iterative two-stage Bayesian approach. ROC curve analyses and logistic regressions was used to investigate the association of exposure and active disease.ResultsA pharmacokinetic model and a BE were developed that allowed good AUC estimation performance (bias±SD=-0.02±0.15). ROC curve analyses showed that AUC/dose<0.06 and AUC<44 mg*h/L were associated with a good sensitivity and specificity for active disease (78%/94% and 94%/56% respectively). When introduced in a logistic regression model, AUC<44 mg.h/L and AUC/dose<0.06 were associated with an increased risk of active disease (OR=21.2[2.3-196.1], p=0.007; and OR [95%CI]=59.5[5.9-588.2], p=0.0005 respectively).Conclusions The developed pharmacokinetics BE could be used to prospectively test the interest of MPA monitoring for limiting relapse of the disease or its progression.
    British Journal of Clinical Pharmacology 04/2014; · 3.69 Impact Factor
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    ABSTRACT: Different associations between single nucleotide polymorphisms (SNPs) in cellular target, metabolism enzymes or transport proteins, and biopsy-proven acute rejection (BPAR) or adverse events have been reported in transplant patients receiving mycophenolate mofetil. This work aimed to study these in patients on enteric-coated mycophenolate sodium (EC-MPS). The study included 189 renal transplant patients from the DOMINOS trial. Fifteen SNPs in IMPDH2, IMPDH1, ABCC2, SLCO1B3, UGT1A8, UGT1A9, UGT2B7, CYP2C8, HUS1, and IL12A were genotyped in all patients. Associations between SNPs and the first event of BPAR or diarrhea were investigated using multivariate logistic regressions. Associations between SNPs and leukopenia or anemia at nine different visits between days 0 and 190 after transplantation were studied using time-dependent Cox proportional hazards regression models. Multivariate analyses showed that the CYP2C8 rs11572076 wild-type genotype was associated significantly with a lower risk of leukopenia [GG vs. GA: hazard ratio (95% confidence interval) 0.14 (0.03, 0.59), P=0.00783]. Higher EC-MPS doses and the UGT2B7 c.-840 G>A variant allele were associated with an increased risk of anemia [EC-MPS per unit dose increase: 1.004 (1.003, 1.005), P<0.0001; UGT2B7 GA vs. AA: 1.65 (1.12, 2.43), P=0.01043; GG vs. AA: 1.88 (1.23, 2.88), P=0.00343]. However, no significant association was found between any of the SNPs studied and diarrhea or BPAR. Two pharmacogenetic associations reported previously with mycophenolate mofetil were found in a population of 189 renal transplant patients treated with EC-MPS.
    Pharmacogenetics and Genomics 03/2014; · 3.61 Impact Factor
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    ABSTRACT: Blood concentrations of the calcineurin inhibitors (CNIs) cyclosporine and tacrolimus are currently measured to monitor immunosuppression in transplant patients. The measurement of calcineurin (CN) phosphatase activity has been proposed as a complementary pharmacodynamic approach. However, determining CN activity with current methods is not practical. We developed a new method amenable to routine use.METHODS: Using liquid chromatography-multiple reaction monitoring mass spectrometry (LC-MRM-MS), we quantified CN activity by measuring the dephosphorylation of a synthetic phosphopeptide substrate. A stable isotope analog of the product peptide served as internal standard, and a novel inhibitor cocktail minimized dephosphorylation by other major serine/threonine phosphatases. The assay was used to determine CN activity in peripheral blood mononuclear cells (PBMCs) isolated from 20 CNI-treated kidney transplant patients and 9 healthy volunteers.RESULTS: Linearity was observed from 0.16 to 2.5 μ mol/L of product peptide, with accuracy in the 15% tolerance range. Intraassay and interassay recoveries were 100.6 (9.6) and 100 (7.5), respectively. Michaelis-Menten kinetics for purified CN were Km = 10.7 (1.6) μ mol/L, Vmax = 2.8 (0.3) μ mol/min/mg, and for Jurkat lysate, Km = 182.2 (118.0) μ mol/L, Vmax = 0.013 (0.006) μ mol/min/mg. PBMC CN activity was successfully measured in a single tube with an inhibitor cocktail.CONCLUSIONS: Because LC-MRM-MS is commonly used in routine clinical dosage of drugs, this CN activity assay could be applied, with parallel blood drug concentration monitoring, to a large panel of patients to reevaluate the validity of PBMC CN activity monitoring.
    Clinical Chemistry 11/2013; · 7.15 Impact Factor
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    ABSTRACT: Our goal was to demonstrate the feasibility of pelvic magnetic resonance imaging (MRI) in the ewe. Two ewes underwent a pelvic 3 Tesla MRI scan, under light anesthesia, with T2-weighted fast spin-echo images and T1-weighted spoiled gradient-echo images. Multiplan T1 weighted images were also obtained after the intravenous injection of a contrast product. One ewe was anestrous and the other one had undergone ovarian stimulation. No incident occurred during the examination. Both the uterus (with two horns) and the ovaries were identified. The intensity of the endometrial, myometrial and ovarian signals was similar to that encountered in women. The uterus and ovaries could be enhanced in both cases. Pelvic vasculature was also studied. In the case of hormonal stimulation, the endometrium was thicker, follicular growth was identified and enhancement seemed greater. MRI in the ewe is feasible and could be helpful in experimental gynecologic research, especially in uterus transplantation.
    Journal of Obstetrics and Gynaecology Research 09/2013; · 0.84 Impact Factor
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    ABSTRACT: Recent studies have identified new candidate polymorphisms in the genes related to CYP3A activity or calcineurin inhibitor dose requirements in kidney transplant recipients. These genes and polymorphisms are CYP3A4 (cytochrome P450, family 3, subfamily A, polypeptide 4) (rs35599367-C>T; *22); POR [P450 (cytochrome) oxidoreductase] (rs1057868-C>T; *28); and PPARA (peroxisome proliferator-activated receptor alpha) (rs4253728-G>A). We investigated the impact of these polymorphisms on sirolimus (SRL) in vitro hepatic metabolism, SRL trough concentrations (C0), and SRL adverse events in kidney transplant recipients.METHODS: The clinical study included 113 stable kidney transplant patients switched from a calcineurin inhibitor to SRL (SRL C0 measured at 1, 3, and 6 months thereafter). We investigated SRL metabolism in vitro using human liver microsomes derived from individual donors (n = 31). Microsomes and patients were genotyped by use of Taqman® allelic discrimination assays. The effects of polymorphisms and covariates were studied using multilinear regression imbedded in linear mixed-effect models or logistic regressions.RESULTS: In vitro, the CYP3A4*22 allele resulted in approximately 20% lower metabolic rates of SRL (P = 0.0411). No significant association was found between CYP3A4, CYP3A5, or PPARA genotypes and SRL dose, C0, or C0/dose in kidney transplant patients. POR*28 was associated with a minor but significant decrease in SRL log-transformed C0 [CT/TT vs CC, β = -0.15 (0.05); P = 0.0197] but this did not have any impact on the dose administered, which limited the relevance of the finding. After adjustment for nongenetic covariates and correction for false discovery finding, none of the single-nucleotide polymorphisms tested showed significant association with SRL adverse events.CONCLUSIONS: These recently described polymorphisms do not seem to substantially influence the pharmacokinetics of SRL or the occurrence of SRL adverse events in kidney transplant recipients.
    Clinical Chemistry 08/2013; · 7.15 Impact Factor
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    ABSTRACT: OBJECTIVES:: Since 2007, a number of transplantation centers have been routinely using an expert system for tacrolimus (TAC) dose adjustment in kidney allograft recipients, based on PK modeling and Bayesian estimation for area-under-the-curve (AUC) determination. This has allowed the setting up of a large database of TAC pharmacokinetic profiles and AUC values, a part of which was analyzed here. METHODS:: We retrospectively studied 2030 requests posted by 21 different centers for routine TAC dose adjustment in 1000 different adult renal transplant patients (not enrolled in any kind of concentration-controlled clinical trial). For each request, the following information was obtained: time elapsed since transplantation, TAC daily dose, calculated AUC, and trough concentration (C0). RESULTS:: The dose-standardized exposure to TAC significantly and progressively increased in the months after transplantation: from month (M) 1 to M9 C0/dose increased from 2.33 to 3.44 mcg·L·mg and AUC/dose from 43.1 to 64.2 mcg·h·L·mg, respectively. On the contrary, in patients beyond the first year whose C0 or AUC was in the target range, the odds of remaining in this range were high for a long time period, suggesting a low intrapatient variability in the stable phase. Regression analyses showed that the correlation between C0 and AUC was better in the first 3-month period (r² = 0.76) than later on (r² ≤ 0.67). Using the regression equations obtained, AUC ranges corresponding to different applicable C0 targets were calculated. CONCLUSIONS:: From a large number of kidney graft recipients, we have estimated the relationships between C0 and AUC, modeled the evolution of TAC exposure with time and defined AUC targets that could be useful to lead further controlled-concentration trials and improve routine TAC therapeutic drug monitoring.
    Therapeutic drug monitoring 05/2013; · 2.43 Impact Factor
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    ABSTRACT: This study aimed to investigate the association between longitudinal exposure to mycophenolic acid (MPA) and acute rejection (AR) risk in the first year after renal transplantation, and to propose MPA exposure targets conditionally to this association. A joint model, adjusted for monitoring strategy (fixed-dose versus concentration-controlled) and recipient age, was developed; it combined a mixed-effects model to describe the whole pattern of MPA exposure (i.e. area under the concentration-time curve -AUC-) and a survival model. MPA AUC thresholds were determined using time-dependent Receiver-Operating Characteristics (ROC) curves. Data from 490 adult renal-transplant recipients, representative of the general population of adult renal-transplant patients (i.e. including patients considered at low immunological risk-enrolled in the OPERA trial- as well as second renal transplant and patients co-treated by either cyclosporine or tacrolimus), were analyzed. A significant association was found between the longitudinal exposure to MPA (MPA AUCs=f(t)) and AR (p=0.0081), and validated by bootstrapping. A significant positive correlation was observed between time post-transplantation and ROC thresholds which increased in average from 35mg.h/L in the first days to 41mg.h/L beyond six months post-transplantation (p<0.001). Using a new modeling approach which recognizes the repeated measures in a same patient, this study supports the association between MPA exposure and AR.
    Pharmacological Research 04/2013; · 4.35 Impact Factor
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    ABSTRACT: This work rationalizes the glucuronidation process (one of the reactions of the phase II metabolism) for drugs having a carboxylic acid moiety. At this stage, acylglucuronides (AG) metabolites are produced, that have largely been reported in the literature for various drugs (e.g., mycophenolic acid (MPA), diclofenac, ibuprofen, phenylacetic acids). The competition between migration and hydrolysis is rationalized by adequate quantum calculations, combing MP2 and density functional theory (DFT) methods. At the molecular scale, the former process is a real rotation of the drug around the glucuconic acid. This chemical-engine provides four different metabolites with various toxicities. Migration definitely appears feasible under alkaline conditions, making proton release from the OH groups. The latter reaction (hydrolysis) releases the free drug, so the competition is of crucial importance to tackle drug action and elimination. From the theoretical data, both migration and hydrolysis appear kinetically and thermodynamically favored, respectively.
    Journal of Molecular Modeling 02/2013; · 1.98 Impact Factor
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    ABSTRACT: BACKGROUND AND OBJECTIVES: Therapeutic drug monitoring of ciclosporin has been recognized as an essential tool in the management of allograft transplant recipients, as it could help improve their outcome. However, there is still no consensus about the optimal method for monitoring ciclosporin after thoracic transplantation. Better knowledge of the pharmacokinetics of ciclosporin in thoracic transplant patients and design of tools dedicated to ciclosporin monitoring could help its practice and its outcome in this population of patients. The aims of this study were to (i) investigate the population pharmacokinetics of ciclosporin in thoracic (heart or lung) transplant patients and study the influence of a range of potential covariates, including demographic, clinical and genetic factors, on pharmacokinetic parameters; and (ii) develop a Bayesian estimator able to predict the individual pharmacokinetic parameters and exposures indices in this population of patients. METHODS: The analysis was performed with 187 full pharmacokinetic profiles obtained in 57 lung and 19 heart transplant patients within the first year post-transplantation. A population pharmacokinetic model was developed by non-linear mixed-effects modelling using NONMEM(®) (version 7.1) from an index dataset (118 profiles). On the basis of this population model and a limited number of blood samples, a Bayesian estimator able to determine ciclosporin area under the blood concentration-time curve (AUC) during a dosage interval was built and evaluated in the validation dataset (69 profiles). RESULTS: Ciclosporin pharmacokinetics were described using a two-compartment model with time-lagged first order absorption and first-order elimination. The final population model included sex as a covariate: ciclosporin apparent oral clearance was on average 37 % faster in male than in female patients (34.8 vs. 25.4 L/h, p < 0.001). Good predictive performance of the Bayesian estimator was obtained using three blood concentrations measured at 40 min, 2 h and 4 h post-dose, with a non-significant bias of -5 % between the estimated and the reference trapezoidal AUC and a good precision (relative mean square error = 13 %). CONCLUSION: Ciclosporin population pharmacokinetic analysis in thoracic transplant patients (including patients with cystic fibrosis) showed a significant influence of sex on apparent clearance. The Bayesian estimator developed in this study yielded accurate prediction of ciclosporin exposure in this population throughout the first year post-transplantation. This tool may allow routine ciclosporin dose individualization.
    Clinical Pharmacokinetics 02/2013; · 5.49 Impact Factor
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    ABSTRACT: Background: Ethylglucuronide (EtG) determination is increasingly used in clinical and forensic toxicology to document ethanol consumption. The enzymes involved in EtG production, as well as potential interactions with common drugs of abuse, have not been extensively studied. Methods: Activities of human liver (HLM), kidney (HKM) and intestinal (HIM) microsomes, as well as of twelve major human recombinant UDP-glucuronosyltransferases (UGTs), toward ethanol (50 and 500 mM) were evaluated in vitro using liquid chromatography-tandem mass spectrometry. Enzyme kinetic parameters were determined for pooled microsomes and recombinant UGTs with significant activity. Individual contributions of UGTs were estimated using the relative activity factor (RAF) approach, proposed for scaling activities obtained with cDNA-expressed enzymes to HLM. Interaction of morphine, codeine, lorazepam, oxazepam, nicotine, cotinine, cannabinol and cannabidiol (5, 10, 15 mg/L) with ethanol (1.15, 4.6, 11.5 g/L; i.e. 25, 100, 250 mM) glucuronidation was assessed using pooled HLM. Results: Ethanol glucuronidation intrinsic clearance (Cl(int)) was 4- and 12.7- times higher for HLM than for HKM and HIM, respectively. All recombinant UGTs, except UGT1A1, 1A6 and 1A10, produced EtG in detectable amounts. UGT1A9 and 2B7 were the most active enzymes, each accounting for 17% and 33% of HLM Cl(int), respectively. Only cannabinol and cannabidiol significantly affected ethanol glucuronidation. Cannabinol increased ethanol glucuronidation in a concentration-dependent manner, whereas cannabidiol significantly inhibited EtG formation in a non-competitive manner (IC(50)=1.17 mg/L; Ki=3.1 mg/L). Conclusions: UGT1A9 and 2B7 are the main enzymes involved in ethanol glucuronidation. In addition, our results suggest that cannabinol and cannabidiol could alter significantly ethanol glucuronidation.
    Drug metabolism and disposition: the biological fate of chemicals 12/2012; · 3.74 Impact Factor
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    ABSTRACT: Except adoption, absolute uterine factor infertility lacks solution in case of motherhood desire. Gestational surrogacy is still not approved in France. Over the last decade, uterus transplantation experimentation made advances. Data from animal research, progress in immunosuppressive treatment and knowledge about pregnancy after transplantation provide a scenario in which a human allotransplantation project can become reality.
    Gynécologie Obstétrique & Fertilité 11/2012; 40(11):691–694. · 0.55 Impact Factor
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    ABSTRACT: Except adoption, absolute uterine factor infertility lacks solution in case of motherhood desire. Gestational surrogacy is still not approved in France. Over the last decade, uterus transplantation experimentation made advances. Data from animal research, progress in immunosuppressive treatment and knowledge about pregnancy after transplantation provide a scenario in which a human allotransplantation project can become reality.
    Gynécologie Obstétrique & Fertilité 10/2012; · 0.55 Impact Factor
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    ABSTRACT: The mammalian target of rapamycin (m-TOR) inhibitor sirolimus is an immunosuppressive drug used in kidney transplantation. m-TOR binds with Raptor and phosphorylates p70S6 kinase, a protein involved in numerous cell signalling pathways. We examined the association of candidate polymorphisms in m-TOR, Raptor and p70S6K, sirolimus dose and exposure, and other time-independent as well as time-dependent covariates, with sirolimus-induced adverse events in kidney transplant recipients. This study included a first group of 113 patients, switched from a calcineurin inhibitor to sirolimus, and a validation group of 66 patients from another clinical trial, with the same immunosuppressive regimen. The effects of gene polymorphisms and covariates on the total cholesterol, LDL cholesterol, triglycerides, haemoglobin, cutaneous adverse events, oedemas and infections were studied using multilinear regression, or logistic regression imbedded in linear mixed-effect models. An m-TOR variant haplotype was significantly associated with a decrease in haemoglobin levels in the two populations of patients (discovery group: β=-0.82 g/dl, P=0.0076; validation group: β=-1.58 g/dl, P=0.0308). Increased sirolimus trough levels were significantly associated with increased total cholesterol levels (discovery group: β=0.02 g/l, P<0.0001; validation group: β=0.02 g/l, P=0.0002) and triglyceride levels (discovery group: β=0.02 g/l, P=0.0059; validation group: β=0.05 g/l, P=0.0370). Sirolimus trough levels were also associated with an increased risk for cutaneous adverse events [odds ratio=1.97, 95% confidence interval (1.32-1.94), P=0.0009] and oedemas [odds ratio=1.16, 95% confidence interval (1.03-1.30), P=0.01342] in the discovery group, but this was not confirmed in the validation group. These results provide evidence of an association between an m-TOR haplotype and a decrease in haemoglobin in renal transplant recipients.
    Pharmacogenetics and Genomics 08/2012; 22(10):725-32. · 3.61 Impact Factor
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    ABSTRACT: This article describes the development of a procedure for the simultaneous evaluation of the activity of six different uridine diphosphate (UDP)-glucuronyltransferases (UGTs) in human liver microsomes (HLMs). The method consists of incubations of probe substrates for UGT1A1 (etoposide), UGT1A3 (chenodeoxycholic acid), UGT1A4 (trifluoperazine), UGT1A6 (serotonin), UGT1A9 (mefenamic acid), and UGT2B7 (azidothymidine) with HLMs. The six substrates were divided into three different incubations (etoposide + mefenamic acid; chenodeoxycholic acid + serotonin + azidothymidine; and trifluoperazine alone), the media of which were pooled before analysis. Glucuronide formation rates were determined in a single run of 20 min using a validated liquid chromatography-tandem mass spectrometry method. No significant difference was observed between glucuronidation activities measured using the current procedure and individual incubations of the probes. The method was used successfully for the determination of UGT activities in 44 individual HLM preparations and for the phenotyping of preparations predicted to have altered UGT1A1 and UGT2B7 activities because of known genetic polymorphisms.
    Analytical Biochemistry 05/2012; 427(1):52-9. · 2.58 Impact Factor
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    ABSTRACT: Nephrotoxicity is an adverse event that strongly limits the use of the immunosuppressant cyclosporine in solid organ transplantation and the precise molecular mechanisms underlying this toxicity remain unclear. MS-based proteomic analysis of the secretome of HEK-293 renal cells exposed to cyclosporine was performed to identify changes in protein secretion, as a first step to discover potential biomarkers of such nephrotoxicity. To detect and quantify the perturbed proteins in the culture medium we used SILAC and nano-scale liquid chromatography followed by MALDI-TOF/TOF mass spectrometry. Among 106 proteins identified, 80 were quantified in both forward/reverse SILAC experiments and quantitative proteomic analysis revealed altered levels of expression for 24 secreted proteins. These included the down-regulation of a number of extracellular matrix/cell adhesion components, and the up-regulation of secreted cyclophilins A and B, macrophage inhibition factor and phosphatidylethanolamine-binding protein 1. These changes in protein secretion were not prevented by co-incubation with the antioxidant N-acetylcysteine, suggesting that they were not triggered by cyclosporine-induced oxidative stress. The results from the present study provide important new knowledge to gain insights into the molecular mechanisms of cyclosporine-related toxicity. Some of the proteins identified here should be tested as potential biomarkers of cyclosporine nephrotoxicity in subsequent clinical studies.
    Journal of proteomics 04/2012; 75(12):3674-87. · 5.07 Impact Factor

Publication Stats

3k Citations
701.69 Total Impact Points


  • 2014
    • French Institute of Health and Medical Research
      Lutetia Parisorum, Île-de-France, France
  • 1997–2014
    • University of Limoges
      • Faculté de Médecine
      Limages, Limousin, France
  • 2004–2013
    • Unité Inserm U1077
      Caen, Lower Normandy, France
  • 2012
    • University of Lille Nord de France
      Lille, Nord-Pas-de-Calais, France
  • 2002–2012
    • Centre Hospitalier Universitaire de Limoges
      • Department of Pharmacology, Toxicology and Pharmacovigilance
      Limoges, Limousin, France
  • 2009
    • University of Grenoble
      Grenoble, Rhône-Alpes, France
  • 2006
    • Assistance Publique Hôpitaux de Marseille
      • Service de médecine légale
      Marseille, Provence-Alpes-Cote d'Azur, France
    • Université Victor Segalen Bordeaux 2
      • Institut de Santé Publique d'Epidémiologie et de Développement (ISPED)
      Bordeaux, Aquitaine, France
  • 2002–2005
    • University of Tours
      Tours, Centre, France