Quantitative Proteomics-Based Blood-Brain Barrier Study

Area of Science:

• Neuroscience
• Pharmacology
• Proteomics

Background:

• Understanding drug permeability across central nervous system (CNS) barriers is crucial for drug discovery, especially in CNS diseases.
• Molecular mechanisms at CNS barriers, like the blood-brain barrier (BBB), are vital for therapeutic development.

Purpose of the Study:

• To elucidate drug permeability and molecular mechanisms at human CNS barriers using quantitative proteomics.
• To compare transporter and receptor expression and function between animal models and humans, and in vitro versus in vivo systems.

Main Methods:

• Quantitative proteomics techniques were applied to blood-brain barrier (BBB) studies.
• Investigated transport systems at the human BBB, focusing on protein expression levels and functions.
• Validated in vitro models for reconstructing in vivo drug efflux activity, including P-glycoprotein (P-gp).

Main Results:

• Clarified quantitative differences in transporter and receptor expression between species and experimental systems.
• Demonstrated accurate reconstruction of in vivo P-gp efflux activity from in vitro systems in various models.
• Discovered Claudin-11 as a tight junction molecule involved in CNS barrier disruption in multiple sclerosis.
• Identified P-gp dysfunction leading to excessive glucocorticoid brain entry and nerve damage, treatable by targeting Abl/Src kinases.

Conclusions:

• Targeting tight junctions and transporters at CNS barriers offers potential therapeutic strategies for CNS diseases.
• Quantitative proteomics provides novel insights into CNS barrier function and disease mechanisms.
• The study highlights the importance of accurate in vitro models for predicting in vivo drug transport.