Froidevaux-Klipfel L.,University Paris - Sud |
Poirier F.,University Paris - Sud |
Boursier C.,University Paris - Sud |
Crepin R.,University Paris - Sud |
And 4 more authors.
Proteomics | Year: 2011
Cell resistance to low doses of paclitaxel (Taxol) involves a modulation of microtubule (MT) dynamics. We applied a proteomic approach based on 2-DE coupled with MS to identify changes in the MT environment of Taxol-resistant breast cancer cells. Having established a proteomic pattern of the microtubular proteins extracted from MDA-MB-231 cells, we verified by Western blotting that in resistant cells, α- and β-tubulins (more specifically the βIII and βIV isotypes) increased. Interestingly, four septins (SEPT2, 8, 9 and 11), which are GTPases involved in cytokinesis and in MT/actin cytoskeleton organization, were overexpressed and enriched in the MT environment of Taxol-resistant cells compared to their sensitive counterpart. Changes in the MT proteome of resistant cells also comprised increased kinesin-1 heavy chain expression and recruitment on MTs while dynein light chain-1 was downregulated. Modulation of motor protein recruitment around MTs might reflect their important role in controlling MT dynamics via the organization of signaling pathways. The identification of proteins previously unknown to be linked to taxane-resistance could also be valuable to identify new biological markers of resistance. © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Perdiz D.,University Paris - Sud |
Mackeh R.,University Paris - Sud |
Pous C.,University Paris - Sud |
Pous C.,Laboratoire Of Biochimie Hormonologie |
Baillet A.,University Paris - Sud
Cellular Signalling | Year: 2011
Microtubules are highly dynamic polymers of α/β tubulin heterodimers that play key roles in cell division and in organizing cell cytoplasm. Although they have been discovered more than two decades ago, tubulin post-translational modifications recently gained a new interest as their role was increasingly highlighted in neuron differentiation and neurodegenerative disorders. Here, we specifically focus on tubulin acetylation from its discovery to recent studies that provide new insights into how it is regulated in health and disease and how it impacts microtubule functions. Even though new mechanisms involving tubulin acetylation are regularly being uncovered, the molecular links between its location inside the microtubule lumen and its regulators and effectors is still poorly understood. This review highlights the emerging roles of tubulin acetylation in multiple cellular functions, ranging from cell motility, cell cycle progression or cell differentiation to intracellular trafficking and signalling. It also points out that tubulin acetylation should no longer be seen as a passive marker of microtubule stability, but as a broad regulator of microtubule functions. © 2010 Elsevier Inc.
Jday-Daly I.,Laboratoire Of Biochimie Generale |
Augereau-Vacher C.,Laboratoire Of Biochimie |
De Curraize C.,Laboratoire Of Biochimie Metabolique |
Fonfrede M.,Laboratoire Of Biochimie Metabolique |
And 3 more authors.
Annales de Biologie Clinique | Year: 2011
As part of a tender AP-HP Paris Hospitals, an assessment of the reliability record of five blood glucose monitoring systems (BGMSs) (Optium Xceed (Abbott), Contour TS (Bayer), One Touch Ultra (Lifescan), Stat Strip Xpress (Nova) and Accu Check (Roche) and an evaluation of their sensitivity to changes in hematocrit were conducted in 4 hospitals of Paris. In terms of inaccuracy, all BGMSs have submitted CV repetability under the limits of acceptability. One BGMS (Lifescan) presented a CV of reproducibility outside limit of acceptability (13.1%). The inaccuracy was measured by a comparison method on multiparameter analyser relative to the hexokinase method for two sites, the glucose oxidase for the two others. The coefficients of correlation varied from 0.8405 to 0.9303. However, according to both defined acceptability criteria (absolute value difference between the result acquired on analyzer and those determined with the BGMS), the percentage of results outside acceptability was above 20% for two BGMSs (Abbott and Lifescan). Similarly, a net effect of changes in hematocrit was observed on the results of those two BGMSs.BGMSNovawas the most reliable, because of the correction device for hematocrit and blank substractions owed to interferences. In terms of expertise, BGMSs Nova and Roche have been selected with the best analytical performance and practicability satisfactory. In the future, accreditation with standard NF/EN 22870 requested for point of care testing, will require a close collaboration between biologists and clinicians to establish a system of strict quality control to detect deviations of these BGMSs.
Brassier A.,University of Paris Descartes |
Boyer O.,University of Paris Descartes |
Valayannopoulos V.,University of Paris Descartes |
Ottolenghi C.,University of Paris Descartes |
And 17 more authors.
Molecular Genetics and Metabolism | Year: 2013
Introduction: Patients with methylmalonic acidemia (MMA) may develop many complications despite medical treatment, in particular, severe central nervous system damage and chronic kidney disease (CKD). A kidney transplant may partially correct the metabolic dysfunctions. Liver, kidney and combined liver-kidney transplantations have been advocated but no guidelines are available to identify the most suitable organ to transplant. Patients and methods: Four patients with MMA (mut° phenotype) received a kidney graft because of repeated metabolic decompensations, with progression to CKD in 3 patients (end-stage kidney disease in two patients and CKD stage III in one patient with an estimated glomerular filtration rate [eGFR] of 40ml/min/1.73m2) but normal renal function in one (eGFR of 93ml/min/1.73m2) before transplantation. Results: The medium age at transplantation was 7.9. y (5-10.2) and the median follow-up was 2.8. years (1.8-4.6). Renal transplantation improved the relevant metabolic parameters in 4/4 patients and renal function in the patients with CKD. Plasma and urinary MMA levels immediately decreased and remained normal or subnormal (mean values of plasma MMA before transplantation 1530. μmol/L versus 240. μmol/L after transplantation, and mean values of urine MMA before transplantation 4700. mmol/mol creatinine versus 2300. mmol/mol creatinine after transplantation). No further acute metabolic decompensation was observed and protein-intake was increased from 0.60 to 0.83. g/Kg/day. One patient transplanted at age 9.7. years developed a hepatoblastoma at age 11. years with subsequent neurological complications and eventually died. The three other patients are alive. Two of them remained neurologically stable. The 3rd patient who displayed choreoathetosis transiently improved his neurological condition immediately after transplantation and then remained stable. Conclusion: Kidney transplantation represents an interesting alternative therapeutic option in methylmalonic aciduria, for renal complications but also as a "cellular therapy" that may significantly reduce metabolic decompensations and hospitalizations. However, further neurological impairment remains possible. © 2013.
Tebani A.,Laboratoire Of Biochimie Hormonologie |
Schlemmer D.,Laboratoire Of Biochimie Hormonologie |
Imbard A.,Laboratoire Of Biochimie Hormonologie |
Rigal O.,Laboratoire Of Biochimie Hormonologie |
And 2 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2011
The measurement of urine sialic acid (N Acetylneuraminic Acid: Neu5Ac) is useful for screening sialic acid storage disorders. We developed a new LC MS/MS method for the determination of a sialic acid. Urine samples were analyzed, after an HCl n-Butanol derivatization step, by a reverse phase based high-performance liquid chromatography method using 1,2,3- 13C 3 N-Acetyl-d-neuraminic Acid ( 13C-Neu5Ac) as an internal standard. Selective detection was performed by tandem mass spectrometry using an electrospray source operating in positive ionization mode employing multiple reactions monitoring to monitor N-Acetylneuraminic Acid and the internal standard. The transitions m/z 366→330 and 369→333 for Neu5Ac and 13C-Neu5Ac were respectively monitored. The limit of the method quantification was 1.40μM of N-Acetylneuraminic Acid and the calibration curve showed a good linearity up to 1000μM. The within assay precision and accuracy of the method ranged from 3.22 to 5.95% and 98.69 to 109.18%, respectively and the between assay precision and accuracy ranged, respectively, from 5.15 to 7.65% and 96.14 to 102.30%. The method can be applied for the determination of N-Acetylneuraminic Acid concentrations in urine and other biological fluids (e.g., amniotic and peritoneal fluids). © 2011 Elsevier B.V.
Kaminsky P.,Nancy University Hospital Center |
Acquaviva-Bourdain C.,Lyon University Hospital Center |
Jonas J.,Nancy University Hospital Center |
Pruna L.,Nancy University Hospital Center |
And 4 more authors.
Muscle and Nerve | Year: 2011
Introduction: Multiple acyl-coenzyme A dehydrogenase deficiency (MADD), also called glutaric aciduria type II, is an inherited metabolic disorder resulting from a deficiency in electron transfer flavoprotein (ETF) or of its ubiquinone oxidoreductase (ETF-QO). It usually occurs in the neonatal period or in early infancy and, very rarely, in adolescents and young adult patients. Methods: We report the case of a 55-year-old woman who developed a painful subacute myopathy. Results: Lipid accumulation was found at biopsy. MADD was confirmed by plasma acylcarnitine profile and by assessment of ETF-QO activity in muscle. Conclusions: This study demonstrates that metabolic myopathies usually found in infancy may be also diagnosed in older patients. MADD may be easily treated by riboflavin and coenzyme Q10 and therefore should be included in the differential diagnosis of adult-onset painful myopathy. © 2011 Wiley Periodicals, Inc.
Chevenne D.,Laboratoire Of Biochimie Hormonologie |
Deghmoun S.,French Institute of Health and Medical Research |
Coric L.,Laboratoire Of Biochimie Hormonologie |
Nicolas M.,Laboratoire Of Biochimie Hormonologie |
Levy-Marchal C.,French Institute of Health and Medical Research
Clinical Biochemistry | Year: 2011
Objectives: Assessment of the analytical performance of the Total Proinsulin ELISA Kit (Millipore) and determination of reference values. Design and methods: Imprecision, specificity, antibodies interference and reference values in normoglycaemic non-obese adults were determined. Results: The inter-assay CV is <. 6.9%, the limits of detection and quantification are 0.2 and 0.6 pmol/L. Molar cross-reactivity of split proinsulins varies from 103 to 92.5%. The interference of anti-(pro)insulin antibodies can be eliminated with the use of polyethylene glycol. The reference values are 2.7-14.2. pmol/L at fasting, 8.5-56.5. pmol/L at T30 min and 11.9-70.5. pmol/L at T120 min during an OGTT. Conclusion: The reference values established for this kit, which showed good analytical performances, allow for a better assessment of pathologies associated with increased proinsulinaemia. © 2011 The Canadian Society of Clinical Chemists.
Froidevaux-Klipfel L.,French Institute of Health and Medical Research |
Targa B.,French Institute of Health and Medical Research |
Cantaloube I.,French Institute of Health and Medical Research |
Ahmed-Zaid H.,French Institute of Health and Medical Research |
And 3 more authors.
Oncotarget | Year: 2015
The mechanisms of cancer cell adaptation to the anti-microtubule agents of the taxane family are multifaceted and still poorly understood. Here, in a model of breast cancer cells which display amplified microtubule dynamics to resist Taxol®, we provide evidence that septin filaments containing high levels of SEPT9_i1 bind to microtubules in a way that requires tubulin long chain polyglutamylation. Reciprocally, septin filaments provide a scaffold for elongating and trimming polyglutamylation enzymes to finely tune the glutamate side-chain length on microtubules to an optimal level. We also demonstrate that tubulin retyrosination and/or a high level of tyrosinated tubulin is crucial to allow the interplay between septins and polyglutamylation on microtubules and that together, these modifications result in an enhanced CLIP-170 and MCAK recruitment to microtubules. Finally, the inhibition of tubulin retyrosination, septins, tubulin long chain polyglutamylation or of both CLIP-170 and MCAK allows the restoration of cell sensitivity to taxanes, providing evidence for a new integrated mechanism of resistance.
Roussel J.,Montpellier University |
Labarthe F.,French Institute of Health and Medical Research |
Thireau J.,Montpellier University |
Ferro F.,Montpellier University |
And 12 more authors.
Heart Rhythm | Year: 2016
Background Short QT syndrome is associated with an increased risk of cardiac arrhythmias and unexpected sudden death. Until now, only mutations in genes encoding the cardiac potassium and calcium channels have been implicated in early T-wave repolarization. Objective The purpose of this study was to confirm a relationship between a short QT syndrome and carnitine deficiency. Methods We report 3 patients affected by primary systemic carnitine deficiency and an associated short QT syndrome. Ventricular fibrillation during early adulthood was the initial symptom in 1 case. To confirm the relationship between carnitine, short QT syndrome, and arrhythmias, we used a mouse model of carnitine deficiency induced by long-term subcutaneous perfusion of MET88. Results MET88-treated mice developed cardiac hypertrophy associated with a remodeling of the mitochondrial network. The continuous monitoring of electrocardiograms confirmed a shortening of the QT interval, which was negatively correlated with the plasma carnitine concentration. As in humans, such alterations coincided with the genesis of ventricular premature beats and ventricular tachycardia and fibrillation. Conclusion Altogether, these results suggest that long-chain fatty acid metabolism influence the morphology and the electrical function of the heart. © 2016 Heart Rhythm Society.
PubMed | Laboratoire Of Biochimie Hormonologie
Type: Journal Article | Journal: Clinical biochemistry | Year: 2011
Assessment of the analytical performance of the Total Proinsulin ELISA Kit (Millipore) and determination of reference values.Imprecision, specificity, antibodies interference and reference values in normoglycaemic non-obese adults were determined.The inter-assay CV is <6.9%, the limits of detection and quantification are 0.2 and 0.6 pmol/L. Molar cross-reactivity of split proinsulins varies from 103 to 92.5%. The interference of anti-(pro)insulin antibodies can be eliminated with the use of polyethylene glycol. The reference values are 2.7-14.2 pmol/L at fasting, 8.5-56.5 pmol/L at T30 min and 11.9-70.5 pmol/L at T120 min during an OGTT.The reference values established for this kit, which showed good analytical performances, allow for a better assessment of pathologies associated with increased proinsulinaemia.