Characterization of Caspase-2 Inhibitors Based on Specific Sites of Caspase-2-Mediated Proteolysis

Bresinsky M, Strasser JM, Hubmann A, Vallaster B, McCue WM, Fuller J, Singh G, Nelson KM, Cuellar ME, Finzel BC, Ashe KH, Walters MA, Pockes S. Characterization of Caspase-2 Inhibitors Based on Specific Sites of Caspase-2-Mediated Proteolysis. Archiv der Pharmazie. 2022;355(9):e2200095. PMID: 35642311. DOI: 10.1002/ardp.202200095.

Summary

This study advanced caspase-2 inhibitor discovery by designing peptides based on naturally occurring caspase-2 cleavage sequences. The authors synthesized 53 molecules and evaluated their potency, selectivity, and binding characteristics using pharmacological, molecular modeling, and crystallographic methods. Although caspase-2 selectivity remained moderate for some analogs, the work revealed key sequence requirements for caspase-2 recognition and showed that five-residue motifs are important for efficient inhibition.

Key Findings

  • Fifty-three peptide analogs were synthesized and tested.
  • Natural caspase-2 cleavage sites informed inhibitor design.
  • Five-residue motifs appeared important for caspase-2 affinity.
  • Some analogs showed strong caspase-3 selectivity, clarifying selectivity determinants.

Impact on the Caspase-2/Tau Program

This paper refined structure-activity relationships for caspase-2 inhibitor development. It helped define the sequence and binding-site features needed to improve potency and selectivity.