Analytical and Bioanalytical Chemistry

, Volume 405, Issue 5, pp 1705–1712 | Cite as

Investigation of the metabolism of monepantel in ovine hepatocytes by UHPLC/MS/MS

  • Lucie Stuchlíková
  • Robert Jirásko
  • Ivan Vokřál
  • Jiří Lamka
  • Marcel Špulák
  • Michal Holčapek
  • Barbora Szotáková
  • Hana Bártíková
  • Milan Pour
  • Lenka Skálová
Original Paper


Monepantel (MOP) belongs to a new class of anthelmintic drugs known as aminoacetonitrile derivatives. It was approved for use in veterinary practice in Czech Republic in 2011. So far, biotransformation and transport of MOP in target animals have been studied insufficiently, although the study of metabolic pathways of anthelmintics is very important for the efficacy of safety of therapy and evaluation of the risk of drug–drug interactions. The aim of this study was to identify MOP metabolites and to suggest the metabolic pathways of MOP in sheep. For this purpose, primary culture of ovine hepatocytes was used as a model in vitro system. After incubation, medium samples and homogenates of hepatocytes were extracted separately using solid-phase extraction. Analysis was performed using a hybrid quadrupole-time-of-flight analyzer with respect to high mass accuracy measurements in full scan and tandem mass spectra for the confirmation of an elemental composition. The obtained results revealed S-oxidation to sulfoxide and sulfone and arene hydroxylation as MOP phase I biotransformations. From phase II metabolites, MOP glucuronides, sulfates, and acetylcysteine conjugates were found. Based on the obtained results, a scheme of the metabolic pathway of MOP in sheep has been proposed.


Monepantel Aminoacetonitrile derivatives Ultrahigh-performance liquid chromatography/mass spectrometry Biotransformation Drug metabolism 



Aminoacetonitrile derivatives


Bovine serum albumin


Dimethyl sulfoxide


Ethylene glycol-bis (β-aminoethyl ether) N,N,N´,N´-tetraacetic acid


Electrospray ionization


High-performance liquid chromatography




Monepantel with hydroxylation


Monepantel sulfoxide


Monepantel sulfoxide with hydroxylation


Monepantel sulfone


Glucuronide of hydroxylated monepantel sulfone


Monepantel sulfone with hydroxylation


Glucuronide of dihydroxylated monepantel sulfone


Sulfate of hydroxylated monepantel sulfone


Monepantel sulfone conjugated with acetylcysteine


Mass spectrometry


Tandem mass spectrometry


Nuclear magnetic resonance


Pyridinium p-toluenesulfonate


Quadrupole-time-of-flight analyzer




Solid-phase extraction


Potassium tert-butoxide






Ultrahigh-performance liquid chromatography


  1. 1.
    Leathwick DM (2012) Modelling the benefits a new class of anthelmintic in combination. Vet Parasitol 186:93–100CrossRefGoogle Scholar
  2. 2.
    Papadopoulos E (2008) Anthelmintic resistance in sheep nematodes. Small Rumin Res 76:99–103CrossRefGoogle Scholar
  3. 3.
    Gobert NG, Jones MK (2008) Discovering new schistosome drug targets: the role of transcriptomics. Curr Drug Targets 9:922–930CrossRefGoogle Scholar
  4. 4.
    Kaplan RM (2004) Drug resistance in nematodes of veterinary importance: a status report. Trends Parasitol 20:477–481CrossRefGoogle Scholar
  5. 5.
    Kaminsky R, Ducray P, Jung M, Clover R, Rufener L, Bouvier J, Weber SS, Wenger A, Wieland-Berghausen S, Goebel T, Gauvry N, Pautrat F, Skripsky T, Froelich O, Komoin-Oka C, Westlund B, Sluder A, Mäser P (2008) A new class of anthelmintics effective against drug-resistant nematodes. Nature 452:176–180CrossRefGoogle Scholar
  6. 6.
    Ducray P, Gauvry N, Pautrat F, Goebel T, Fruechtel J, Desaules Y, Weber SS, Bouvier J, Wagner T, Froelich O, Kaminsky R (2008) Discovery of amino-acetonitrile derivatives, a new class of synthetic anthelmintic compounds. Bioorg Med Chem Lett 18:2935–2938CrossRefGoogle Scholar
  7. 7.
    Kinsella B, Byrne P, Cantwell H, McCormack M, Furey A, Danaher M (2011) Determination of the new anthelmintic monepantel and its sulfone metabolite in milk and muscle using a UHPLC-MS/MS and QuEChERS method. J Chromatogr B 879:3707–3713CrossRefGoogle Scholar
  8. 8.
    Karadzovska D, Seewald W, Browning A, Smal M, Bouvier J, Giraudel JM (2008) Pharmacokinetics of monepantel and its sulfone metabolite, monepantel sulfone, after intravenous and oral administration in sheep. J Vet Pharmacol Ther 32:359–367CrossRefGoogle Scholar
  9. 9.
    Holčapek M, Kolářová L, Nobilis M (2008) High-performance liquid chromatography-tandem mass spectrometry in the identification and determination of phase I and phase II drug metabolites. Anal Bioanal Chem 391:59–78CrossRefGoogle Scholar
  10. 10.
    Vokřál I, Jedličková V, Jirásko R, Stuchlíková L, Bártíková H, Skálová L, Lamka J, Holčapek M, Szotáková B (2011) Metabolic fate of ivermectin in host (Ovis aries) and parasite (Haemonchus contortus). Vet Parasitol 185:168–174CrossRefGoogle Scholar
  11. 11.
    Vokřál I, Jirásko R, Jedličková V, Bártíková H, Skálová L, Lamka J, Holčapek M, Szotáková B (2012) The inability of tapeworm Hymenolepis diminuta and fluke Dicrocoelium dendriticum to metabolize praziquantel. Vet Parasitol 185:168–174CrossRefGoogle Scholar
  12. 12.
    Holčapek M, Jirásko R, Lísa M (2012) Recent developments in liquid chromatography-mass spectrometry and related techniques. J Chromatogr A 1259:3–15CrossRefGoogle Scholar
  13. 13.
    Liu DQ, Hop CE (2005) Strategies for characterization of drug metabolites using liquid chromatography-tandem mass spectrometry in conjunction with chemical derivatization and on-line H/D exchange approaches. J Pharm Biomed Anal 37:1–18CrossRefGoogle Scholar
  14. 14.
    Liu X, Jia L (2007) The conduct of drug metabolism studies considered good practice (I): analytical systems and in vivo studies. Curr Drug Metab 8:815–821CrossRefGoogle Scholar
  15. 15.
    Jirásko R, Holčapek M, Nobilis M (2011) Identification of phase I and phase II metabolites of benfluron and dimefluron in rat urine using high-performance liquid chromatography/tandem mass spectrometry. Rapid Commun Mass Sp 25:2153–2162CrossRefGoogle Scholar
  16. 16.
    Staack RF, Hopfgartner G (2007) New analytical strategies in studying drug metabolism. Anal Bioanal Chem 388:1365–1380CrossRefGoogle Scholar
  17. 17.
    Berry MN, Edwards AM, Barritt GJ (1991) Laboratory techniques in biochemistry and molecular biology. In: Burdow RH, van Knippenberg PH (eds) Isolated hepatocytes preparation, properties and applications. Elsevier Science, Amsterdam, pp 15–35Google Scholar
  18. 18.
    Baliharová V, Velík J, Savlík M, Szotáková B, Lamka J, Tahotná L, Skálová L (2004) The effects of fenbendazole, flubendazole and mebendazole on activities of hepatic cytochromes P450 in pig. J Vet Pharmacol Ther 27:85–90CrossRefGoogle Scholar
  19. 19.
    Velík J, Baliharová V, Skálová L, Szotáková B, Wsól V, Lamka J (2003) Stereospecific biotransformation of albendazole in muflon and rat-isolated hepatocytes. J Vet Pharmacol Ther 26:297–302CrossRefGoogle Scholar
  20. 20.
    Montesissa C, Anfossi P, Van’t Klooster G, Mengelers M (1996) The use of cultured hepatocytes from goats and cattle to investigate xenobiotic oxidative metabolism. Vet Res Commun 20:449–460CrossRefGoogle Scholar
  21. 21.
    Parkinson A (2001) In: Klaassen CD (ed) Casarett & Doull’s toxicology—the basic science of poisons. New York, McGraw-HillGoogle Scholar
  22. 22.
    Nobilis M, Anzenbacher P, Pastera J, Svoboda Z, Hrubý K, Květina J, Ubik K, Trejtnar F (1996) Study of the biotransformation of a potential benzocfluorene antineoplastic using high-performance liquid chromatography with high-speed-scanning ultraviolet detection. J Chromatogr B 681:143–151CrossRefGoogle Scholar
  23. 23.
    Holčapek M, Jirásko R, Lísa M (2010) Basic rules for the interpretation of atmospheric pressure ionization mass spectra of small molecules. J Chromatogr A 25:3908–3921Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2012

Authors and Affiliations

  • Lucie Stuchlíková
    • 1
  • Robert Jirásko
    • 2
  • Ivan Vokřál
    • 3
  • Jiří Lamka
    • 3
  • Marcel Špulák
    • 4
  • Michal Holčapek
    • 2
  • Barbora Szotáková
    • 1
  • Hana Bártíková
    • 1
  • Milan Pour
    • 4
  • Lenka Skálová
    • 1
  1. 1.Department of Biochemical Sciences, Faculty of Pharmacy in Hradec KrálovéCharles University in PragueHradec KrálovéCzech Republic
  2. 2.Department of Analytical Chemistry, Faculty of Chemical TechnologyUniversity of PardubicePardubiceCzech Republic
  3. 3.Department of Pharmacology and Toxicology, Faculty of Pharmacy in Hradec KrálovéCharles University in PragueHradec KrálovéCzech Republic
  4. 4.Department of Inorganic and Organic Chemistry, Faculty of Pharmacy in Hradec KrálovéCharles University in PragueHradec KrálovéCzech Republic

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