Expanding the MiniAp-4 BBB-shuttle family: Evaluation of proline cis-trans ratio as tool to fine-tune transport

J Pept Sci. 2019 May;25(5):e3172. doi: 10.1002/psc.3172.

Abstract

Venoms have recently emerged as a promising field in drug discovery due to their good selectivity and affinity for a wide range of biological targets. Among their multiple potential applications, venoms are a rich source of blood-brain barrier (BBB) peptide shuttles. We previously described a short nontoxic derivative of apamin, MiniAp-4, which can transport a wide range of cargoes across the BBB. Here, we have studied the conformation of the proline residue of a range of MiniAp-4 analogues by high-field NMR techniques, with the aim to identify whether there is a direct relation between the cis/trans population and a range of features, such as the capacity to transport molecules across a human-based cellular model and stability in various media. The most promising candidate showed improved transport properties for a relevant small fluorophore.

Keywords: apamin; blood-brain barrier; blood-brain barrier shuttle; brain delivery; central nervous system; venoms.

MeSH terms

  • Apamin / chemistry
  • Apamin / isolation & purification
  • Apamin / metabolism*
  • Biological Transport
  • Blood-Brain Barrier / chemistry
  • Blood-Brain Barrier / metabolism*
  • Cells, Cultured
  • Humans
  • Nuclear Magnetic Resonance, Biomolecular
  • Proline / chemistry
  • Proline / metabolism*
  • Protein Conformation
  • Stereoisomerism

Substances

  • Apamin
  • Proline