DI-UMONS : Dépôt institutionnel de l’université de Mons

Recherche transversale
Rechercher
(titres de publication, de périodique et noms de colloque inclus)
2010-05-19 - Colloque/Présentation - poster - Anglais - 1 page(s)

Henoumont Céline , Vander Elst Luce , Laurent Sophie , Muller Robert , "Effects of nonenzymatic glycosylation on the binding to human serum albumin of some MRI contrast agents" in Contrast-enhanced biomedical imaging, 12th Bi-Annual Conference on Contrast Agents and Multimodal Molecular Imaging, Mons, Belgique, 2010

  • Codes CREF : Résonance magnétique nucléaire (biophysique) (DI131B), Imagerie médicale, radiologie, tomographie (DI3243)
  • Unités de recherche UMONS : Chimie générale, organique et biomédicale (M108)
  • Instituts UMONS : Institut des Sciences et Technologies de la Santé (Santé), Institut des Biosciences (Biosciences)

Abstract(s) :

(Anglais) Purpose : Enhanced nonenzymatic glycosylation of human serum albumin (HSA) is observed for the diabetic patients. This modifies some of the physiological functions of HSA, as the binding of ligands[1,2]. Some gadolinium complexes, usually used as MRI contrast agents, have a high affinity for HSA, which enhances their efficacy. The aim of this study is to evaluate the influence of the glycosylation of HSA on the affinity of some gadolinium chelates. Material and method : This study was performed for Gd-EOB-DTPA[3,4] (Primovist®, Bayer HealthCare), MS-325[5,6] (Vasovist®, Bayer HealthCare) and MP2269[7,8]. The two first complexes were provided by Bayer HealthCare (Berlin, Germany), and MP2269 was provided by Mallinckrodt (Saint-Louis, USA). Non glycosylated and glycosylated human serum albumin were obtained from Sigma (Bornem, Belgium). The study of the interaction of the gadolinium chelates with glycosylated and non glycosylated HSA was performed by the proton relaxometry technique[3,6] at 20 MHz and 310 K (Minispec mq-20, Bruker, Karlsruhe, Germany). NMRD profiles were also recorded on a Stelar relaxometer working between 0.24 mT and 0.24 T (Mede, Italy). Additional points at 0.47 T, 1.41 T and 7.05 T were measured on Minispec mq-20 and mq-60, and on a AMX300 spectrometer (Bruker). Results : The results show a slight decrease of the affinity of Gd-EOB-DTPA and MS-325 for the glycosylated HSA, whereas no effect is observed for MP2269. As it has been shown before that the two first chelates bind on the Suddlow site I of HSA, this could mean that the glycosylation of HSA influences mainly the ligand binding on the Suddlow site I of HSA. The observed effect is however very weak. Conclusion : Globally, the results show a negligible effect of the glycosylation of HSA on the affinity of the three studied contrast agents, which is encouraging for the use of these molecules in diabetic patients. References : [1] Okabe, N.; Yoshida, S. Biol. Pharm. Bull. 1995, 18(1), 154-155. [2] Koizumi, K.; Ikeda, C.; Ito, M.; Suzuki, J.; Kinoshita, T.; Yasukawa, K.; Hanai, T. Biomed. Chromatogr. 1998, 12, 203-210. [3] Vander Elst, L.; Maton, F.; Laurent, S.; Seghi, F.; Chapelle, F.; Muller, R. N. Magn.Reson.Med. 1997, 38, 604-614. [4] Vander Elst, L.; Chapelle, F.; Laurent, S.; Muller, R. N. J.Biol.Inorg.Chem. 2001, 6, 196-200. [5] Lauffer, R. B.; Parmalee, D. J.; Dunham, S. U.; Ouellet, H. S.; Dolan, R. P.; Witte, S.; McMurry, T. J.; Walowitch, R. C. Radiol. 1998, 207, 529-538. [6] Muller, R. N.; Radüchel, B.; Laurent, S.; Platzek, J.; Piérart, C.; Mareski, P.; Vander Elst, L. Eur.J.Inorg.Chem. 1999, 1949-1955. [7] Adzamli, K.; Vander Elst, L.; Laurent, S.; Muller, R. N. Magn.Reson.Mater.Phys.Biol.Med. 2001, 12, 92-95. [8] Adzamli, K.; Spiller, M.; Koenig, S. H. Acad.Radiol. 2002, 9, S11-S16.