Polypeptide delivery across the blood-brain barrier

Area of Science:

• Neuroscience
• Pharmacology
• Cell Biology

Background:

• The blood-brain barrier (BBB) was historically considered impermeable to polypeptides.
• Recent research shows polypeptides can cross the BBB, offering new therapeutic avenues for central nervous system (CNS) disorders.

Purpose of the Study:

• To review the mechanisms of polypeptide interaction with the BBB.
• To discuss advances in the cell biology of polypeptide transport across the BBB.
• To explore the potential of polypeptides as direct treatments for CNS disorders.

Main Methods:

• Review of existing literature on BBB transport mechanisms for polypeptides.
• Analysis of interactions affecting polypeptide passage, including diffusion and facilitated transport.
• Discussion of factors impeding or facilitating polypeptide entry into the CNS.

Main Results:

• Polypeptide interactions with the BBB are diverse, involving simple diffusion, saturable transport, and carrier-mediated mechanisms.
• Factors within the blood or at the BBB endothelial cells can significantly impact polypeptide transport.
• Polypeptides themselves can be therapeutic agents for CNS conditions like neurodegeneration, stroke, and depression.

Conclusions:

• The BBB's permeability to polypeptides has been redefined, opening possibilities for novel drug delivery strategies.
• Understanding BBB transport dynamics is crucial for developing effective polypeptide-based therapies for CNS disorders.
• Further research into BBB cell biology will guide future treatments for neurological and psychiatric conditions.