Traversing the blood-brain barrier is a challenge for drug developers. Now, after testing the method in locusts, a team of engineers shows how an aerosol nasal spray containing Gold nanoparticles may offer non-invasive and rapid way to deliver drugs to the brain.
Researchers from the University of Washington in St. Louis (WUSTL), MO describes the proof-of concept research in the journal Scientific Reports.
For optimal function of the brain, it must operate in a tightly controlled chemical environment that is protected from the more varied fluctuations from the rest of the body. This stable environment is maintained by blood-brain barrier that comprises layers of specialized cells in the inner linings of the small blood vessels in the brain and spinal cord.
This blood-brain barrier prevents toxins from entering the tissues of the brain and spinal cord. Unfortunately, it also keeps out many drugs such as those used to kill cancer cells.
Injections could be used to overcome this barrier; however, such invasive procedures are risky that they can damage tissue and have little control over the distribution of the drugs from the point of injection, says the researchers.
Nose offers easy access to the brain
Nanotechnology gives us the ability to control matter at the atomic and molecular state- to develop new diagnostic tools and treatment. Several nanomaterials have been used to carry drugs to specific targets in organs and tissues. These appear to maximize drug effectiveness while minimizing side effects.
Researchers have noted from various studies that gold nanoparticles have emerged as the material of choice for drug delivery. They are relatively easy to synthesize and customize and they also have good biocompatibility.
Locusts offer a good model of the human blood-brain barrier
Researchers tested the effectiveness of the nanoparticle aerosol in locusts because their blood brain barriers bear similarities to those of humans- especially when going through the nasal route.
In human beings, the nanoparticles have to travel through the olfactory bulb and then the olfactory cortex to reach the brain.
The team exposed the locusts’ antennae to the aerosol and tracked the progress of the tagged nanoparticles. Within a few minutes, the nanoparticles had traversed the insects’ olfactory circuitry, passed through the brain-blood barrier, and suffused the brain tissue.
The team showed that the nanoparticles did not affect the insects’ brain function. They measured the electrophysiological responses of the locusts’ olfactory neurons before and after treatment and found no discernible difference up to several hours afterwards.
The researchers say that the next stage of their research will be to load the nanoparticles with different drugs and use ultrasound to target precise doses to reach specific areas of the brain. Such methods could potentially make a big difference to the treatment of brain tumors.
Blood-brain barrier protects the brain from foreign substances in the blood that may injure the brain. However with nanotechnology, the procedure is non-invasive and also possess little risk and better response times.