Anomalous interaction of tri-acyl ester derivatives of uridine nucleoside with a l-α-dimyristoylphosphatidylcholine biomembrane model: a differential scanning calorimetry study

J Pharm Pharmacol. 2019 Mar;71(3):329-337. doi: 10.1111/jphp.13038. Epub 2018 Nov 20.

Abstract

Objectives: Uridine was conjugated with fatty acids to improve the drug lipophilicity and the interaction with phospholipid bilayers.

Methods: The esterification reaction using carbodiimides compounds as coupling agents and a nucleophilic catalyst allowed us to synthesize tri-acyl ester derivatives of uridine with fatty acids. Analysis of molecular interactions between these tri-acyl ester derivatives and l-α-dimyristoylphosphatidylcholine (DMPC) multilamellar vesicles (MLV) - as a mammalian cell membrane model - have been performed by differential scanning calorimetry (DSC).

Key findings: The DSC thermograms suggest that nucleoside and uridine triacetate softly interact with phospholipidic multilamellar vesicles which are predominantly located between the polar phase, whereas the tri-acyl ester derivatives with fatty acids (myristic and stearic acids) present a strongly interaction with the DMPC bilayer due to the nucleoside and aliphatic chains parts which are oriented towards the polar and lipophilic phases of the phospholipidic bilayer, respectively. However, the effects caused by the tri-myristoyl uridine and tri-stearoyl uridine are different.

Conclusions: We show how the structural changes of uridine modulate the calorimetric behaviour of DMPC shedding light on their affinity with the phospholipidic biomembrane model.

Keywords: anticancer nucleoside; biomembrane models; differential scanning calorimetry; fatty acid; uridine.

MeSH terms

  • Acetates / chemistry*
  • Calorimetry, Differential Scanning / methods
  • Dimyristoylphosphatidylcholine / chemistry*
  • Esters / chemistry*
  • Fatty Acids / chemistry
  • Membranes / chemistry*
  • Models, Theoretical
  • Nucleosides / chemistry*
  • Phospholipids / chemistry
  • Uridine / analogs & derivatives*
  • Uridine / chemistry

Substances

  • Acetates
  • Esters
  • Fatty Acids
  • Nucleosides
  • Phospholipids
  • uridine triacetate
  • Dimyristoylphosphatidylcholine
  • Uridine