Development of a small RGD peptide fibrinogen receptor antagonist with potent antiaggregatory activity in vitro
| Autor: | Fadia E. Ali, A. Nichols, Raul R. Calvo, J. Vasko, Barbara L. Storer, D. Bennett, D. Berry, E. Sorenson, Jeffrey M. Stadel, M. Strohsacker, David Powers, J. Samanen, T T Romoff |
|---|---|
| Rok vydání: | 1991 |
| Předmět: |
Platelet Aggregation
Fibrinogen receptor Molecular Sequence Data Peptide Platelet Membrane Glycoproteins Fibrinogen Peptides Cyclic Structure-Activity Relationship Dogs Drug Stability Drug Discovery medicine Potency Animals Platelet Amino Acid Sequence Receptor chemistry.chemical_classification Tetrapeptide Chemistry Molecular biology Peptide Fragments Biochemistry Cyclization Platelet-rich plasma Molecular Medicine Oligopeptides Platelet Aggregation Inhibitors medicine.drug |
| Zdroj: | Journal of medicinal chemistry. 34(10) |
| ISSN: | 0022-2623 |
| Popis: | The development of potent antithrombotic agents from the fibrinogen platelet receptor binding sequences Fg-alpha 572-575 -Arg-Gly-Asp-Ser- and Fg-gamma 400-411 -HHLGGAKQAGDV, believed to be a cryptic RGD-type sequence, is described. The tetrapeptide Ac-RGDS-NH2 itself is capable of inhibiting platelet aggregation in vitro at high concentrations, IC50 91.3 +/- 0.1 microM [in vitro antiaggregatory activity employing dog platelet rich plasma (PRP)/ADP], due to low platelet fibrinogen receptor affinity, Ki 2.9 +/- 1.9 microM (purified, reconstituted human platelet GPIIb/IIIa), relative to fibrinogen, Ki 38.0 +/- 6.0 nM. The peptide is also unstable to plasma, suffering total loss of in vitro activity upon incubation in PRP for 3 h (T1/2 90 min). Only modest improvements in potency were achieved with linear analogues of Ac-RGDS-NH2, while dramatic results were achieved with cyclic analogues, culminating in the cyclic disulfide Ac-cyclo-S,S-[Cys-(N alpha-Me)Arg-Gly-Asp-Pen]-NH2 (SK&F 106760) with improved plasma stability (100% activity after 3 h), affinity (Ki 58 +/- 20 nM purified human receptor), and potency (IC50 0.36 +/- 0.4 microM dog PRP/ADP). The affinity of this peptide is 2 orders of magnitude greater than that of Ac-RGDS-NH2. The affinity of the analogue is also comparable to fibrinogen. This peptide constitutes a first potent small peptide entry into the class of novel antithrombotic agents called fibrinogen receptor antagonists. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|