What do bubbles, sound waves, and Michael J. Fox have in common?
I found the answer during a presentation at the Columbia University Medical Center. Amanda Buch, a Bridge to Ph.D. student in biomedical engineering and neuroscience at the university, revealed the common denominator in the Late Night Science talk, “Focused Ultrasound: How Sound Can Heal Your Brain.”
Buch explained that the biomedical and neuroscience labs she works in are focused on studying Alzheimer’s and Parkinson’s disease. The work of actor Michael J. Fox is one degree of separation away; besides being known for his role as Marty McFly in Back to the Future, Fox heads the Michael J. Fox Foundation for Parkinson’s Research. The actor was diagnosed with the disease at age 30 (the average age of onset for the disease is 60), and now his foundation is a source of funding for focused ultrasound research, including research at Columbia.
So that’s how Fox fits in the picture. How about sound waves?
It’s important to clarify that we’re not referencing the sound waves made by your favorite band. We’re referring to ultrasound (the type of sound that has high frequencies, short wave lengths, and is not audible to human ears). Ultrasound has a lot of uses—sonar for submarines, echolocation for bats, and imaging of unborn babies (maybe you’ve seen ultrasound images posted by excited parents on Facebook!).
Ultrasound has not traditionally been applied to brain research because skull thickness impedes wave transmission. Because of engineering advances, though, we are now able to deflect the waves appropriately through the intact skull and target specific areas in the brain. Focused ultrasound is now used in neurological research to treat essential tremor, Parkinson’s disease, brain tumors, epilepsy, and Alzheimer’s disease.
What’s more, ultrasound is non-invasive and highly localized. What this means in practice is that treatment using focused ultrasound doesn’t require invasive brain surgery, or an expensive MRI machine. Rather, focused ultrasound uses an ultrasound transducer, much like the wand used to image a fetus in a woman’s womb. It is similarly non-invasive because it is simply placed on the skin.
But, what about the bubbles?
Focused ultrasound has three potential uses for healing our brains: 1) destroying damaged brain tissue, 2) controlling dysfunctional signaling, and 3) improving localized drug delivery. It’s this last one that Buch helped us delve into (and that uses bubbles).
Researchers have identified specific structures in the brain that are associated with Alzheimer’s and Parkinson’s, but have struggled to treat these areas in a localized way.
In this method of treatment, microbubbles are injected into the blood stream along with a chosen drug. The focused ultrasound is aimed specifically at a targeted area in the brain and, by making the bubbles vibrate at the same frequency as the ultrasound waves, the blood-brain-barrier is loosened by the bubbles bumping up against it. The therapeutic drug passes through the barrier and treats the specific area.
Buch is working in the labs of two principle investigators, Elisa Konofagou, Ph.D., and Vincent Ferrera, Ph.D. at Columbia University. Visit the Columbia University Neuroscience Outreach website for more scientific riddles and the opportunity to tour a lab.
– Betsy Grether