|A silk adenosine-releasing implant designed to treat epilepsy.--Courtesy of NIH|
Researchers looking to stem the progression of epilepsy have turned to drug-releasing brain implants made of silk, safely reducing the number of seizures by up to four times in animal trials.
The Legacy Research Institute, Oregon Health & Science University and Tufts University team developed an adenosine-releasing silk implant to deliver the compound that lowers neuronal excitability and helps stop seizures. Past studies have shown that low levels of adenosine may be linked to epilepsy.
The biodegradable implant dissolves after releasing adenosine in the brain for up to 10 days, according to a National Institutes of Health report. The adenosine affects DNA methylation in the brain, a process that involves blocking portions of DNA to resemble healthy brains.
Part of what causes epilepsy, scientists believe, is an increase in "mossy fiber sprouting," which the NIH defines as "the foundation of new excitatory circuits in the part of the brain where seizures commonly originate." Rats implanted with the silk implant showed less sprouting than animals not given adenosine over a three month period.
"Based on our findings that 10 days of adenosine delivery prevented the sprouting of mossy fibers for at least three months in rats, we predict that the benefits of our adenosine therapy may extend even longer," lead researcher Detlev Boison said in a statement. "However, this assumption needs to be validated in long-term experiments that go beyond three months."
"Clinical applications could be the prevention of epilepsy following head trauma or the prevention of seizures that often--in about 50% of patients--follow conventional epilepsy surgery," Boison added. "In this case, adenosine-releasing silk might be placed into the resection cavity in order to prevent future seizures."
The team will conduct further studies to determine the dose, the duration of release and best points of intervention for the device, as well as how long it would safely last in humans.
- here's the NIH report