Nav: Home

Lighting up cardiovascular problems using nanoparticles

December 09, 2019

Heart disease and stroke are the world's two most deadly diseases, causing over 15 million deaths in 2016 according to the World Health Organization. A key underlying factor in both of these global health crises is the common condition, atherosclerosis, or the build-up of fatty deposits, inflammation and plaque on the walls of blood vessels. By the age of 40, around half of us will have this condition, many without symptoms.

A new nanoparticle innovation from researchers in USC Viterbi's Department of Biomedical Engineering may allow doctors to pinpoint when plaque becomes dangerous by detecting unstable calcifications that can trigger heart attacks and strokes.

The research ­­-- from Ph.D. student Deborah Chin under the supervision of Eun Ji Chung, the Dr. Karl Jacob Jr. and Karl Jacob III Early-Career Chair, in collaboration with Gregory Magee, assistant professor of clinical surgery from Keck School of Medicine of USC -- was published in the Royal Society of Chemistry's Journal of Materials Chemistry B.

When atherosclerosis occurs in coronary arteries, blockages due to plaque or calcification-induced ruptures can lead to a clot, cutting blood flow to the heart, which is the cause of most heart attacks. When the condition occurs in the vessels leading to the brain, it can cause a stroke.

"An artery doesn't need to be 80 percent blocked to be dangerous. An artery with 45% blockage by plaques could be more rupture-prone," Chung said. "Just because it's a big plaque doesn't necessarily mean it's an unstable plaque."

Chung said that when small calcium deposits, called microcalcifications, form within arterial plaques, the plaque can become rupture prone.

However, identifying whether blood vessel calcification is unstable and likely to rupture is particularly difficult using traditional CT and MRI scanning methods, or angiography, which has other risks.

"Angiography requires the use of catheters that are invasive and have inherent risks of tissue damage," said Chin, the lead author. "CT scans on the other hand, involve ionizing radiation which can cause other detrimental effects to tissue."

Chung said that the resolution limitations of traditional imaging offers doctors a "bird's eye view" of larger-sized calcification, which may not necessarily be dangerous. "If the calcification is on the micro scale, it can be harder to pick out," she said.

The research team developed a nanoparticle, known as a micelle, which attaches itself and lights up calcification to make it easier for smaller blockages that are prone to rupture to be seen during imaging.

Chin said the micelles are able to specifically target hydroxyapatite, a unique form of calcium present in arteries and atherosclerotic plaques.

"Our micelle nanoparticles demonstrate minimal toxicity to cells and tissue and are highly specific to hydroxyapatite calcifications," Chin said. "Thus, this minimizes the uncertainty in identifying harmful vascular calcifications."

The team has tested their nanoparticle on calcified cells in a dish, within a mouse model of atherosclerosis, as well as using patient-derived artery samples provided by vascular surgeon, Magee, which shows their applicability not only in small animals but in human tissues.

"In our case, we demonstrated that our nanoparticle binds to calcification in the most commonly used mouse model for atherosclerosis and also works in calcified vascular tissue derived from patients," Chin said.

Chung said that the next step for the team was to harness the micelle particles to be used in targeted drug therapy to treat calcification in arteries, rather than just as means of detecting the potential blockages.

"The idea behind nanoparticles and nanomedicine is that it can be a carrier like the Amazon carrier system, shuttling drugs right to a specific address or location in the body, and not to places that you don't want it to go to," Chung said.

"Hopefully that can allow for lower dosages, but high efficacy at the disease site without hurting normal cells and organ processes," she said.
-end-


University of Southern California

Related Nanoparticles Articles:

Nanoparticles: Acidic alert
Researchers of Ludwig-Maximilians-Universitaet (LMU) in Munich have synthesized nanoparticles that can be induced by a change in pH to release a deadly dose of ionized iron within cells.
3D reconstructions of individual nanoparticles
Want to find out how to design and build materials atom by atom?
Directing nanoparticles straight to tumors
Modern anticancer therapies aim to attack tumor cells while sparing healthy tissue.
Sweet nanoparticles trick kidney
Researchers engineer tiny particles with sugar molecules to prevent side effect in cancer therapy.
A megalibrary of nanoparticles
Using straightforward chemistry and a mix-and-match, modular strategy, researchers have developed a simple approach that could produce over 65,000 different types of complex nanoparticles.
Dialing up the heat on nanoparticles
Rapid progress in the field of metallic nanotechnology is sparking a science revolution that is likely to impact all areas of society, according to professor of physics Ventsislav Valev and his team at the University of Bath in the UK.
Illuminating the world of nanoparticles
Scientists at the Okinawa Institute of Science and Technology Graduate University (OIST) have developed a light-based device that can act as a biosensor, detecting biological substances in materials; for example, harmful pathogens in food samples.
What happens to gold nanoparticles in cells?
Gold nanoparticles, which are supposed to be stable in biological environments, can be degraded inside cells.
Lighting up cardiovascular problems using nanoparticles
A new nanoparticle innovation that detects unstable calcifications that can trigger heart attacks and strokes may allow doctors to pinpoint when plaque on the walls of blood vessels becomes dangerous.
Cutting nanoparticles down to size -- new study
A new technique in chemistry could pave the way for producing uniform nanoparticles for use in drug delivery systems.
More Nanoparticles News and Nanoparticles Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Our Relationship With Water
We need water to live. But with rising seas and so many lacking clean water – water is in crisis and so are we. This hour, TED speakers explore ideas around restoring our relationship with water. Guests on the show include legal scholar Kelsey Leonard, artist LaToya Ruby Frazier, and community organizer Colette Pichon Battle.
Now Playing: Science for the People

#568 Poker Face Psychology
Anyone who's seen pop culture depictions of poker might think statistics and math is the only way to get ahead. But no, there's psychology too. Author Maria Konnikova took her Ph.D. in psychology to the poker table, and turned out to be good. So good, she went pro in poker, and learned all about her own biases on the way. We're talking about her new book "The Biggest Bluff: How I Learned to Pay Attention, Master Myself, and Win".
Now Playing: Radiolab

Uncounted
First things first: our very own Latif Nasser has an exciting new show on Netflix. He talks to Jad about the hidden forces of the world that connect us all. Then, with an eye on the upcoming election, we take a look back: at two pieces from More Perfect Season 3 about Constitutional amendments that determine who gets to vote. Former Radiolab producer Julia Longoria takes us to Washington, D.C. The capital is at the heart of our democracy, but it's not a state, and it wasn't until the 23rd Amendment that its people got the right to vote for president. But that still left DC without full representation in Congress; D.C. sends a "non-voting delegate" to the House. Julia profiles that delegate, Congresswoman Eleanor Holmes Norton, and her unique approach to fighting for power in a virtually powerless role. Second, Radiolab producer Sarah Qari looks at a current fight to lower the US voting age to 16 that harkens back to the fight for the 26th Amendment in the 1960s. Eighteen-year-olds at the time argued that if they were old enough to be drafted to fight in the War, they were old enough to have a voice in our democracy. But what about today, when even younger Americans are finding themselves at the center of national political debates? Does it mean we should lower the voting age even further? This episode was reported and produced by Julia Longoria and Sarah Qari. Check out Latif Nasser's new Netflix show Connected here. Support Radiolab today at Radiolab.org/donate.