Discovery of Tarantula Venom-Derived NaV1.7-Inhibitory JzTx-V Peptide 5-Br-Trp24 Analogue AM-6120 with Systemic Block of Histamine-Induced Pruritis.Wu, B., Murray, J.K., Andrews, K.L., Sham, K., Long, J., Aral, J., Ligutti, J., Amagasu, S., Liu, D., Zou, A., Min, X., Wang, Z., Ilch, C.P., Kornecook, T.J., Lin, M.J., Be, X., Miranda, L.P., Moyer, B.D., Biswas, K.
(2018) J. Med. Chem. 61: 9500-9512
- PubMed: 30346167
- DOI: 10.1021/acs.jmedchem.8b00736
- PubMed Abstract:
Inhibitors of the voltage-gated sodium channel Na <sub>V </sub>1.7 are being investigated as pain therapeutics due to compelling human genetics. We previously identified Na <sub>V </sub>1.7-inhibitory peptides GpTx-1 and JzTx-V from tarantula venom s ...
Inhibitors of the voltage-gated sodium channel Na V 1.7 are being investigated as pain therapeutics due to compelling human genetics. We previously identified Na V 1.7-inhibitory peptides GpTx-1 and JzTx-V from tarantula venom screens. Potency and selectivity were modulated through attribute-based positional scans of native residues via chemical synthesis. Herein, we report JzTx-V lead optimization to identify a pharmacodynamically active peptide variant. Molecular docking of peptide ensembles from NMR into a homology model-derived Na V 1.7 structure supported prioritization of key residues clustered on a hydrophobic face of the disulfide-rich folded peptide for derivatization. Replacing Trp24 with 5-Br-Trp24 identified lead peptides with activity in electrophysiology assays in engineered and neuronal cells. 5-Br-Trp24 containing peptide AM-6120 was characterized in X-ray crystallography and pharmacokinetic studies and blocked histamine-induced pruritis in mice after subcutaneous administration, demonstrating systemic Na V 1.7-dependent pharmacodynamics. Our data suggests a need for high target coverage based on plasma exposure for impacting in vivo end points with selectivity-optimized peptidic Na V 1.7 inhibitors.
Therapeutic Discovery, Amgen Research , Amgen Inc. , 1120 Veterans Blvd , South San Francisco , California 94080 , United States.