Nous souhaitons la bienvenue à nos deux nouveaux doctorants :
- Jordan Beurton (encadré par A. Boudier et P. Lavalle (INSERM Strasbourg), "Optimisation physicochimique de films nanostructurés pour des applications cardio-vasculaires")
- Sarah El Hajj (encadrée par L. Cannabady-Rochelle (LRGP) et C. Gaucher, "Innovative screening methodology for metal chelating peptides with antioxidant properties using Surface Plasmon Resonance")
L'article "Higher-energy collision dissociation for the quantification by liquid chromatography-tandem ion trap mass spectrometry of nitric oxide metabolites coming from S-nitrosoglutathione in an in vitro model of intestinal barrier" vient de paraître dans le journal "Rapid Communications in Mass Spectrometry"
Auteurs : Haiyan Yu, Justine Bonetti, Caroline Gaucher, Isabelle Fries, Lionel Vernex-Loset, Pierre Leroy, Patrick Chaimbault
Référence de l'article : Rapid Communications in Mass Spectrometry, doi: 10.1002/rcm.8287
Abstract
Rationale
The potency of S‐nitrosoglutathione (GSNO) as a nitric oxide (NO) donor to treat cardiovascular diseases (CVDs) has been highlighted in numerous studies. In order to study its bioavailability after oral administration, which represents the most convenient route for the chronic treatment of CVDs, it is essential to develop an analytical method permitting (i) the simultaneous measurement of GSNO metabolites, i.e. nitrite, S‐nitrosothiols (RSNOs) and nitrate and (ii) them to be distinguished from other sources (endogenous synthesis and diet).
Methods
Exogenous GSNO was labeled with 15N, and the GS15NO metabolites after conversion to nitrite ion were derivatized with 2,3‐diaminonaphthalene. The resulting 2,3‐naphthotriazole was quantified by liquid chromatography‐tandem ion trap mass spectrometry (LC/ITMS/MS) in multiple reaction monitoring mode after Higher‐energy Collision Dissociation (HCD). Finally, the validated method was applied to an in vitro model of intestinal barrier (monolayer of Caco‐2 cells) to study GS15NO intestinal permeability.
Results
A LC/ITMS/MS method based on an original transition (m/z 171 to 156) for sodium 15N‐nitrite, GS15NO and sodium 15N‐nitrate measurements was validated, with recovery of 100.8 ± 3.8, 98.0 ± 2.7 and 104.1 ± 3.3 %, respectively. Intra‐ and inter‐day variabilities were below 13.4 and 12.6 %, and the limit of quantification reached 5 nM (signal over blank = 4). The permeability of labeled GS15NO (10‐100 μM) was evaluated by calculating its apparent permeability coefficient (Papp).
Conclusions
A quantitative LC‐ITMS/MS method using HCD was developed for the first time to selectively monitor GS15NO metabolites. The assay allowed evaluating GS15NO intestinal permeability and situated this drug candidate within the middle permeability class according to FDA guidelines. In addition, the present method has opened the perspective of a more fundamental work aiming at studying the fragmentation mechanism leading to the ion at m/z 156 in HCD tandem mass spectrometry in the presence of acetonitrile.
L'article "Synthesis of novel mono and bis nitric oxide donors with high cytocompatibility and release activity" vient de paraître dans le journal "Bioorganic & Medicinal Chemistry Letters"
Auteurs : Tanya Sahyoun, Caroline Gaucher, Yi Zhou, Naïm Ouaini, Raphaël Schneider and Axelle Arrault
Référence de l'article : Bioorganic & Medicinal Chemistry Letters, DOI: 110.1016/j.bmcl.2018.09.009
Highlights
•A series of aromatic and aliphatic mono-amidoximes and bis-amidoximes were synthesized.
•Amodoximes were tested for their NO release ability on rat liver microsomes and human vascular cells.
•Amidoximes are cytocompatible with human vascular smooth muscle cells.
•Mono-amidoximes 2a and 2b exhibit high NO release.
•Bis-amidoxime 2d releases the same amount of NO than 2a and 2b at a twice lower concentration.
Abstract :
Four compounds bearing amidoxime functions were synthetized: (1) 2a-b bearing an aromatic amidoxime function, (2) 2c bearing an aliphatic amidoxime function, and (3) 2d bearing aromatic and aliphatic amidoximes functions. The ability of these compounds to release NO was evaluated in vitro using the oxidative metabolism of cytochrome P450 from rat liver microsomes. Results obtained demonstrate that all amidoximes were able to release NO with a highest amount of NO produced by the 2a aromatic amidoxime. Moreover, all amidoximes exhibit cytocompatibility with human aorta smooth muscle cells. Using intracellular S-nitrosothiol formation as a marker of NO bioavailability, compounds 2a-c were demonstrated to deliver a higher amount of NO in the intracellular environment than the reference. Considering that the concentration of the bis-amidoxime 2d was two times lower that than of 2a and 2b, we can assume that 2d is the most potent molecule among the tested compounds for NO release.
L'article "Labeling nitrogen species with the stable isotope 15N for their measurement by separative methods coupled with mass spectrometry: A review" vient de paraître dans le journal "Talanta".
Auteurs : Haiyan Yu, Patrick Chaimbault, Igor Clarot, Zilin Chen, and Pierre Leroy
Référence de l'article : Talanta, Volume 191 (2019), Pages 491-503, DOI 10.1016/j.talanta.2018.09.011
Abstract :
Nitrogen and its numerous hydrogenated and oxygenated derivatives are of main importance in our environment and in living cells as well in both qualitative and quantitative aspects. Their monitoring is needed to evaluate all disturbances occurring in the nitrogen cycle and in pathophysiological events related to variations of nitric oxide (NO) bioavailability. Many analytical methods are devoted to the measurement of nitrogen species, especially those related to NO, in the environmental, biological and pharmacological fields, and they have already been compiled and discussed in numerous reviews. Nitrogen isotope (15N) is stable and has a low level of natural abundance. Labeling nitrogen species with 15N associated with mass spectrometry (MS) gives rise to more mechanistic information and improved analytical performances compared to conventional methods. The present review is dedicated to the 15N labeling of related nitrogen species to monitor their interconversion and metabolism, the different chemical probes used for their derivatization and the corresponding separative methods coupled with MS for analyzing resulting adducts. The fragmentation mode of the different adducts and the resulting selectivity and sensitivity are discussed.
Nous souhaitons la bienvenue à Arnaud Pallotta, qui rejoint notre équipe en tant que Maître de Conférences en Chimie Analytique.
Haiyan YU soutiendra sa thèse de doctorat intitulée "Etude de la biodisponibilité orale du S-nitrosoglutathion au moyen de modèles de la barrière intestinale par chromatographie en phase liquide couplée à la spectrométrie de masse après marquage par l’isotope 15 de l’azote" le mercredi 29 août à 14 h dans la salle du Conseil (Faculté de Pharmacie, rue Lionnois) à Nancy.
Le jury est composé de :
- Mme Emilie DESTANDAU (Rapporteur, MCU, ICOA UMR 7311, Institut de Chimie Organique et Analytique, Université d'Orléans, Orléans)
- Mme Elke RICHLING (Rapporteur, PR, Technical University of Kaiserslautern, Allemagne)
- Mr Pierre LEROY (Examinateur, PR, EA 3452 CITHEFOR, Université de Lorraine, Nancy, directeur de thèse)
- Mr Patrick CHAIMBAULT (Examinateur, PR, LCP-A2MC, EA 4632, Université de Lorraine, Metz, co-directeur de thèse)
Justine BONETTI, étudiante en 1ère année de doctorat en co-tutelle avec l’Université de Pise, a obtenu une bourse d’aide à la mobilité de l’université Franco-Italienne (programme VINCI), dans le cadre du projet « Potentiel thérapeutique des S-nitrosothiols dans la prévention de l’athérosclérose : modulation de la métaplasie des monocytes et cellules musculaires lisses en cellules spumeuses ».
L'article "Comparison between two derivatization methods of nitrite ion labeled with 15N applied to liquid chromatography-tandem mass spectrometry" vient de paraître dans le journal "Analytical Methods"
Auteurs : Haiyan Yu, Romain Schmitt, Anne Sapin-Minet, Patrick Chaimbault and Pierre Leroy
Référence de l'article : Analytical Methods, 2018, DOI: 10.1039/C8AY01206G
Abstract :
The fragmentations of the adducts resulting from the derivatization of nitrite ion by Griess method (formation of an azo compound) and 2,3-diaminonaphthalene (formation of 2,3-naphthotriazole (NAT)) were studied by tandem mass spectrometry (MS/MS). The transition used for quantification was selected according to the highest value of the signal-over-blank ratio (S/B) obtained from each adduct fragmentation. When derivatizing nitrite ion labeled with the stable 15N isotope, followed by liquid chromatography (LC)-MS/MS measurement, the lowest limit of quantification obtained was 5 nM with NAT. The method was applied to study the intestinal permeability of S-nitrosoglutathione, a drug candidate for the chronic treatment of cardiovascular disease.This coumpound was labeled with 15N and its permeability was studied in an ex vivo rat intestine model using an Ussing chamber.
Les conférences auront lieu dans l'Amphithéâtre BRUNTZ– 2ème hall
Le programme est le suivant :
