Atherosclerosis is a condition where an artery-wall thickens as a result of invasion and accumulation of white blood cells and proliferation of intimal-smooth-muscle cell creating a fibrofatty plaque. The condition can lead to a heart attack, as a result of a blood clot which blocks the blood supply to the heart.
To help deal with the disease, researchers have developed special nanoparticles. These particles are designed so that, when they make contact with an atherosclerotic plaque — a fatty clog narrowing a blood vessel, they adhere to the plaque. Once adhered, the nanoparticles proceed to break down the structure. This allows red blood cells to circulate uninhibited, improving the overall flow of blood through the artery.
The newly developed nanoparticles a very small (at just 100 nanometers diameter.) The particles are coated with molecules designed to fix (or ‘tag’) plaque. The molecules can also include dyes, which allow medical technologists to track the movements of the particles. The biding happens in different ways; one such way, according to Science News, is by mimicking natural cholesterol molecules.
The nanoparticles also contain chemicals designed to attack the plaque and break it down. In trials in mice and pigs, the nanoparticles have proved successful.
One area of that needs more fine tuning is ensuring nanoparticles affix to the right materials and with tracking their progress and location in the body. According to Dr. Melina Kibbe of Northwestern University Feinberg School of Medicine in Chicago, this is not straightforward.
In a research note she states: “It took us over a year of trying to find the right targeting [molecule] that would work.”
However, a breakthrough has been achieved through the use of a collagen-binding protein with nitric oxide. By fashioning a nanofiber, rather than a sphere, the research group found the nanoparticle adheres to plaque better. Once bound, the nitric oxide plays a role in breaking down the plaque. In trials, the nanofibers were found to bind to plaque within an hour of injection.
More work is required, however, before the nanoparticles can be used with human patients.
Although nanomedicine is an advancing field, few applications have received regulatory approval. Those that have been approved are primarily for the treatment of cancer. This is largely because the medical technology is an emerging field and more information is needed in relation to medicinal safety.
A key advantage with nanoparticles to treat plaque formation is that it avoids surgery (which may not fully work or lead to risks of post-operative infection) and the use of statins (which carry side-effects and cannot “cure” someone, the drugs merely alleviate the symptoms.) Nanoparticles achieve what statins cannot do, which is to shrink atherosclerotic plaques and eliminate the associated inflammation. These advantages with nanotechnology, along with other innovations, are trending on Twitter #nanotech.
The latest research is published in the journal Antioxiants & Redox Signaling. The research paper is titled “Targeted Nitric Oxide Delivery by Supramolecular Nanoﬁbers for the Prevention of Restenosis After Arterial Injury.”