Scientific Breakthrough – Nanoparticle Eats Plaque Responsible for Heart Attacks

Scientific Breakthrough – Nanoparticle Eats Plaque Responsible for Heart Attacks Graphic © herbshealthhappiness.com
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Heart disease is the leading cause of mortality globally, with the World Health Organization reporting over 17.9 million deaths each year because of cardiovascular diseases. Cardiovascular diseases include disorders that affect the circulatory system or the heart and blood vessels in the body. Furthermore, the WHO reports more than four out of five deaths due to cardiovascular disease are attributed to heart attacks or strokes. ^[1] This is alarming, as a third of these deaths happens to people younger than 70 years old.

Heart Attack And Stroke: What’s The Difference?

Heart attacks and strokes are two different conditions that have a similar underlying pathology – the build-up of plaque in blood vessels, which cuts off the blood and oxygen supply to the cells and tissues.

A heart attack or myocardial infarct happens when there is a build-up of plaque in the blood vessels of the heart which cuts off blood supply to cardiac tissue. When the build-up of plaque happens in the brain and cuts off blood supply to brain tissue, we have stroke or a cerebrovascular infarct.

The medical term for plaque build-up is atherosclerosis, or the build-up of fat, cholesterol, and other substances in the blood vessels causing the formation of plaque and inflammatory lesions. ^[2] When blood flow through these vessels are affected, our cells and tissues of can become deprived of oxygen, causing cell dysfunction and even cell death. The death of cells and tissues in the heart and brain are irreversible and can lead to severe morbidities and even mortality.

Nanotechnology And Arterial Plaque

Despite the sci-fi “aura” around notechnology, it is very real and has been used in healthcare since the early 1990’s. In a groundbreaking study published by Flores, et. al. in 2020, genetically engineered nanoparticles were found to reduce arterial plaque formation without damaging healthy cells or tissues. ^[3]

Flores, et. al. focused on the concept that the body has a naturally occurring process called phagocytosis, that should be able to clear out foreign bodies or material from the body. This is part and parcel of our immunity, so why doesn’t it work on plaque formation in heart disease?

The researchers found that plaque is able to evade the body’s natural phagocytic process called efferocytosis (“to take to the grave”, or the clearance of inflammatory, dying cells in the body) because plaque formations release an increased amount of CD47. CD47 is a molecule that hides plaque from our immune system, basically tricking it into believing that plaque should not be removed. Interestingly, this is the same molecule released by cancer cells that help them evade the body’s natural immunity.

In order to target plaque removal, the researchers engineered nanoparticles that interrupted the release of CD47 by inflammatory cells found in plaque formations. This stimulated efferocytosis and reduced size of the plaque formation and resulting lesions. Furthermore, because the nanoparticles were engineered specifically to target inflammatory cells in plaque, they did not affect the healthy cells and tissues surrounding the affected area, which was the problem typically faced by previous systemic traditional therapies.

The researchers dubbed their nanoparticle a “Trojan horse” that was able to infiltrate plaque and promote clearance of diseased cells, thereby reducing the risk for cardiovascular disease.

Other Studies On Nanoparticles And Heart Disease:

Detection and Imaging Through Nanotechnology:

Zhang, et. al. published a study in 2017 that also focused on the ability of nanoparticles to detect and treat heart disease, specifically atherosclerosis. ^[4] The researchers found studies published as early as 2000 and 2001 that used nanoparticles to detect thrombi and lesions in blood vessels. Other studies were able to use nanoparticles in the imaging of these atherosclerotic lesions. On the other hand, studies were also able to use nanoparticles in targeted treatment, specifically targeted anti-inflammatory treatment using nanoparticles. The researchers concluded that nanoparticles had very promising results with targeted therapies in vitro and in vivo.

Nanoparticle Pharmacotherapy:

Going by the same route taken by Flores, et. al., another study was published in 2020 by Gao, et. al that used nanoparticles in cases of atherosclerosis. ^[5] This time nanoparticles were used in targeted pharmacotherapy to address inflammatory lesions in atherosclerotic vessels. Instead of stimulating the body’s natural efferocytosis response, the researchers used nanoparticles coated in macrophage membrane to deliver the drug or medication directly to the affected site. This was also able to prevent damage to healthy cells seen in traditional therapies (like oral medications to reduce cholesterol) in managing heart disease. This nanoparticle-driven drug delivery system was able to reduce the plaque area from approximately 20% to 8%.

miNano:

In 2021, Luo, et. al. conducted a study using a genetically engineered nanoparticle they dubbed the ‘miNano’ on cholesterol crystals found in plaque. ^[6] miNano is a phospholipid-based and high-density lipoprotein (HDL)-like nanoparticle that is designed to bind to cholesterol crystals. Naturally-occurring HDL is able to dissolve cholesterol crystals and reduce the inflammatory response in plaque formations – the characteristic the miNano was patterned after. The miNano was able to accumulate in these plaque formations and act similar to natural HDL, suppressing the inflammatory response and inhibiting atherosclerosis. The researchers found that the miNano particles were also absent in healthy cell walls, only targeting or depositing specifically in plaque.

Summary:

With nanotechnology and nanoparticles being around for almost three decades and their resulting breakthroughs in modern medicine for the past two of those decades, successfully managing what used to be a deadly condition could be easily within our reach. In vitro and in vivo studies on nanoparticles and heart disease have been very promising, as seen in the results of the recent studies published in the past few years. Diagnosing and treating atherosclerosis could potentially be done without harming healthy cells or tissues, which is typically seen in traditional medical treatment for cardiovascular disease. Targeted drug therapy through nanoparticles could improve the safety and efficacy of treating heart disease, improving the quality of life and reducing the economic burden of those affected by it.

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