When it comes to the treatment of severe Parkinson's disease, electrical deep brain stimulation (DBS) is a commonly used technique. It does have some serious drawbacks, however, which is why scientists are now looking to tiny wirelessly activated magnets instead.
In order for DBS to be carried out on a patient, electrodes must be surgically implanted in the subthalamic nucleus (STN) region of their brain, then hard-wired to a pacemaker-like battery/control unit implanted under the skin on their chest. Those electrodes proceed to periodically activate STN nerve cells, reducing motor symptoms of Parkinson's such as tremors, rigidity and involuntary movements.
Not only is the implantation procedure quite invasive, but because the electrodes aren't small enough to affect nothing but the STN cells, side effects such as brain tissue damage may occur. For these reasons, DBS is usually reserved for late-stage and/or treatment-resistant Parkinson's disease.
Seeking a kinder, gentler alternative, researchers from Korea's Yonsei University created minuscule magnets tagged with antibodies. The devices are known as nanoscale magnetic force actuators, or m-Torquers.
These m-Torquers were injected into the subthalamic nucleus of mice with early- and late-stage Parkinson's disease. Due to the fact that the antibodies were selected because they stick to the surface of STN cells specifically, the m-Torquers only adhered to those cells, leaving all others alone.
Additionally, some of the STN cells had previously been genetically engineered to activate when twisted. This twisting effect was achieved by exposing the subthalamic nucleus to a weak externally applied rotating magnetic field. Doing so caused all of the m-Torquers to swivel back and forth, twisting their respective STN cells in the process.
In lab tests, mice that received the treatment showed a two-fold improvement in locomotor activity and motor balance, as compared to an untreated control group of Parkinson's-afflicted mice. What's more, no significant brain tissue damage was observed, plus the therapeutic effect persisted for some time after the treatment had ceased.
A paper on the research, which was led by Minsuk Kwak and Jinwoo Cheon, was recently published in the journal Nano Letters.
Source: American Chemical Society
