Researchers from the University of Rochester Medical Center (URMC) have discovered a way to potentially deliver drugs to the brain more efficiently.

Due to the difficulty of getting enough drugs into the brain effectively, many therapies for central nervous system diseases have failed in clinical trials. Indeed, the brain is protected by a complex system of molecular gateways, which control what can enter and exit the brain.

The purpose of the blood-brain barrier is to protect the brain against pathogens and toxins that can cause brain infections. At the same time, it allows vital nutrients to enter to maintain levels of hormones, nutrients and water. Therefore, many mental and neurological disorders do not have the possibility to be treated with potential drug treatments: it is estimated that only 2% of therapies enter the organs.

Research from 2015 showed that using an ultrasound to open the blood–brain barrier can improve cognition and decrease the amount of toxic plaque that accumulates in the brain. A further study in 2017 demonstrated ultrasound as a promising tool to open the blood-brain barrier temporarily. They dispute that it can release more therapeutic antibodies to the brain which can improve pathologies of Alzheimer’s and understanding antibody drugs in isolation.

Co-Director of the Centre of Translational Neuromedicine at URMC, and lead author of the study Dr Maiken Nedergaard said, “Improving the delivery of drugs to the central nervous system is a considerable clinical challenge. The findings of this study demonstrate that the brain’s waste removal system could be harnessed to transport drugs quickly and efficiently into the brain.”

Nedergaard’s and URMC’s new research uses the power of the glymphatic system which was discovered in 2012. They were able to temporarily open the blood-brain barrier and inject mice with a hypertonic saline. This triggered an ion imbalance pulling cerebral spinal fluid out of the brain. They “tricked” the blood-brain barrier into allowing the passage of the administered antibodies directly into the cerebral spinal fluid, through the blood by a transporter protein.

As this is happening the glymphatic system flows new cerebral fluid into the brain tissue along with the carried antibodies.

Thanks to the discovery, the way Alzheimer’s, Parkinson’s, ALS and brain cancer are treated could have positive implications.

References

• University of Rochester Medical Center. (https://www.urmc.rochester.edu/news/story/5451/study-points-to-new-method-to-deliver-drugs-to-the-brain.aspx). October 18, 2018. Study Points to New Method to Deliver Drugs to the Brain.
• Forbes. (https://www.forbes.com/sites/robinseatonjefferson/2018/11/18/scientists-discover-a-way-to-get-drugs-to-the-brain-faster-and-more-efficiently/#2bea2f95f95b). November 18, 2018. Robin Seaton Jefferson. Scientists Discover A Way To Get Drugs To The Brain Faster And More Efficiently
• Drug Target Review. (https://www.drugtargetreview.com/news/36234/deliver-blood-brain/). October 19, 2018. Iqra Farooq. Better drug delivery through the blood-brain barrier.