Structural studies of [2′,6′-dimethyl-l-tyrosine1]endomorphin-2 analogues: enhanced activity and cis orientation of the Dmt-Pro amide bond
摘要:
Analogues of endomorphin-2 (EM-2: Tyr-Pro-Phe-Phe-NH2) (1) were designed to examine the importance of each residue on mu-opioid receptor interaction. Replacement of Tyr(1) by 2',6'-dimethyl-L-tyrosine (Dmt) (9-12) exerted profound effects: [Dmt(1)]EM-2 (9) elevated mu-opioid affinity 4.6-fold (K(i)mu = 0.15 nM) yet selectivity fell 330-fold as delta-affinity rose (K(i)delta = 28.2 nM). This simultaneous increased mu- and delta-receptor bioactivities resulted in dual agonism (IC50 = 0.07 and 1.87 nM, respectively). While substitution of Phe(4) by a phenethyl group (4) decreased mu affinity (K(i)mu 13.3 nM), the same derivative containing Dmt (12) was comparable to EM-2 but also acquired weak delta antagonism (pA(2) = 7.05). H-1 NMR spectroscopy revealed a trans configuration (1:2 to 1:3, cis/trans) in the Tyr-Pro amide bond, but a cis configuration (5:3 to 13:7, cis/trans) with Dmt-Pro analogues. (C) 2003 Elsevier Science Ltd. All rights reserved.
Biodegradable Amphipathic Peptide Hydrogels as Extended-Release System for Opioid Peptides
作者:Charlotte Martin、Maria Dumitrascuta、Morgane Mannes、Aquilino Lantero、Dominik Bucher、Katja Walker、Yannick Van Wanseele、Edith Oyen、Sophie Hernot、Ann Van Eeckhaut、Annemieke Madder、Richard Hoogenboom、Mariana Spetea、Steven Ballet
DOI:10.1021/acs.jmedchem.8b01282
日期:2018.11.8
Chronic pain is currently treated with opioids that offer unsatisfactory long-term analgesia and produce serious side effects. There is a clear need for alternative therapies. Herein, peptide-based hydrogels are used as extended-release drug delivery carriers. Two different formulations were developed: the drug is coformulated within the hydrogen the drug is an integral part of the hydrogelator. Both strategies afford a prolonged and significant antinociception up to 72 h after subcutaneous administration in mice.