In vitro membrane permeation studies and in vivo antinociception of glycosylated Dmt1-DALDA analogues

Steven Ballet, Cecilia Betti, Alexandre Novoa, Csaba Tömböly, Carsten Uhd Nielsen, Hans Christian Helms, Anna Lesniak, Patrycja Kleczkowska, Nga N. Chung, Andrzej W. Lipkowski, Birger Brodin, Dirk Tourwé, Peter W. Schiller

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7 Citations (Scopus)


In this study the μ opioid receptor (MOR) ligands DALDA (Tyr-d-Arg-Phe-Lys-NH2) and Dmt1-DALDA (Dmt-d-Arg-Phe-Lys-NH2, Dmt = 2′,6′-dimethyltyrosine) were glycosylated at the N- or C-terminus. Subsequently, the modified peptides were subjected to in vitro and in vivo evaluation. In contrast to the N-terminally modified peptide (3), all peptide analogues derivatized at the C-terminus (4-7) proved to possess high affinity and agonist potency at both MOR and DOR (δ opioid receptor). Results of the Caco-2 monolayer permeation, as well as in vitro blood-brain barrier model experiments, showed that, in the case of compound 4, the glycosylation only slightly diminished the lumen-to-blood and blood-to-lumen transport. Altogether, these experiments were indicative of transcellular transport but not active transport. In vivo assays demonstrated that the peptides were capable of (i) crossing the blood-brain barrier (BBB) and (ii) activating both the spinal ascending as well as the descending opioid pathways, as determined by the tail-flick and hot-plate assays, respectively. In contrast to the highly selective MOR agonist Dmt 1-DALDA 1, compounds 4-7 are mixed MOR/DOR agonists, expected to produce reduced opioid-related side effects.

Original languageEnglish
Pages (from-to)352-357
Number of pages6
JournalACS Medicinal Chemistry Letters
Issue number4
Publication statusPublished - Apr 10 2014



  • Opioid peptides
  • glycosylation
  • in vivo antinociception

ASJC Scopus subject areas

  • Biochemistry
  • Drug Discovery
  • Organic Chemistry

Cite this

Ballet, S., Betti, C., Novoa, A., Tömböly, C., Uhd Nielsen, C., Helms, H. C., Lesniak, A., Kleczkowska, P., Chung, N. N., Lipkowski, A. W., Brodin, B., Tourwé, D., & Schiller, P. W. (2014). In vitro membrane permeation studies and in vivo antinociception of glycosylated Dmt1-DALDA analogues. ACS Medicinal Chemistry Letters, 5(4), 352-357.