Targeted delivery of GDNF through the blood-brain barrier by MRI-guided focused ultrasound

PLoS One. 2012;7(12):e52925. doi: 10.1371/journal.pone.0052925. Epub 2012 Dec 27.

Abstract

Neurotrophic factors, such as glial cell line-derived neurotrophic factor (GDNF), are promising therapeutic agents for neurodegenerative diseases. However, the application of GDNF to treat these diseases effectively is limited because the blood-brain barrier (BBB) prevents the local delivery of macromolecular therapeutic agents from entering the central nervous system (CNS). Focused ultrasound combined with microbubbles (MBs) using appropriate parameters has been previously demonstrated to be able to open the BBB locally and noninvasively. This study investigated the targeted delivery of GDNF MBs through the BBB by magnetic resonance imaging (MRI)-guided focused ultrasound. Evans Blue extravasation and histological examination were used to determine the optimum focused ultrasound parameters. Enzyme-linked immunosorbent assay was performed to verify the effects of GDNF bound on MBs using a biotin-avidin bridging chemistry method to promote GDNF delivery into the brain. The results showed that GDNF can be delivered locally and noninvasively into the CNS through the BBB using MRI-guided focused ultrasound combined with MBs under optimum parameters. MBs that bind GDNF combined with MRI-guided focused ultrasound may be an effective way of delivering neurotrophic factors directly into the CNS. The method described herein provides a potential means of treating patients with CNS diseases.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Blood-Brain Barrier / drug effects*
  • Blood-Brain Barrier / metabolism
  • Brain / drug effects*
  • Brain / metabolism
  • Drug Delivery Systems / methods*
  • Glial Cell Line-Derived Neurotrophic Factor / administration & dosage*
  • High-Energy Shock Waves
  • Magnetic Resonance Imaging / methods
  • Male
  • Microbubbles
  • PC12 Cells
  • Rats
  • Rats, Sprague-Dawley

Substances

  • Glial Cell Line-Derived Neurotrophic Factor

Grants and funding

This work was supported by grants from the National Natural Science Foundation (No. 30970833), National 973 basic research program (No. 2011CB707903), the National Natural Science Foundation (No. 81101048 and No. U1204810), National Postdoctoral Science Foundation (No. 2011M501111), and Shenzhen Basic Research Program (No. JC201005280495A). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.