Building a Better Cyborg Heart

Tuesday - August 8 2023, 15:22 UTC - 1 year ago

A new study has connected digital components with biological cells into a cyborg organoid that can regenerate and repair living hearts. This technology is made up of a mixture of human stem cells and electric-active silicon nanowires, which allows lab-made mini-hearts to better synchronize with the host heart.

The tiny, floating blobs of mini-hearts were straight out of Frankenstein. Made from a mixture of human stem cells and a sprinkle of silicon nanowires, the cyborg heart organoids bizarrely pumped away as they grew inside Petri dishes.

When transplanted into rats with heart injuries they lost their spherical shape, spreading out into damaged regions and connecting with the hosts’ own heart cells. Within a month, the rats regained much of their heart function.

It’s not science fiction. A new study this month linked digital electrical components with biological cells into a cyborg organoid that, when transplanted into animal models of heart failure, melded with and repaired living, beating hearts.

At the heart (cough, pun intended) of the technology are electrically-active biodegradable silicon nanowires. Heart cells synchronize their movement to the beat of electrical activity, producing the standard "ba-bump, ba-bump" rhythm. A dose of nanowires into the organoids acted as a conductor to the symphony, allowing the lab-grown mini-hearts to better synchronize with their hosts.

Compared to standard heart organoids—grown exactly the same way but without the nanowire boost—the cyborg ones could better tolerate the hostile chemical environment inside the heart after a heart attack. They also better connected to their hosts during recovery, fighting off a detrimental side effect often seen after heart injuries.

For now the cyborg heart organoid transplant only works in rats. But it’s just a start.

Heartstopper .

The heart is a trooper. From birth to death, it diligently contracts and releases to pump out blood full of oxygen to the rest of the body. It’s a biological wonder, faithfully lasting over 100 years in centenarians—far longer than most man-made hardware contraptions.

Yet the heart is also a failure point. Heart disease is the leading cause of death worldwide. A main reason is that cardiomyocytes—the "muscle cells" of the heart that contract—have very limited ability to regenerate. When damaged from a heart attack, scar tissue gradually grows around the injured areas, eventually limiting the heart’s ability to contract.

Scientists have long sought to treat heart disease with new, healthy cells. One popular idea is to guide human stem cells to develop into replacement cardiomyocytes. The lab-made heart muscle cells are then injected into damaged areas. Scientist have tested the treatment in a range of animal models of heart disease, including rodents, pigs, and nonhuman primates. But the healthy cells, when confronted with a hostile environment, struggled to survive. Those that did couldn’t reliably recover from heart damage, leading to potential problems with arrhythmia—irregular heartbeats that occur when different portions of the heart can’t beat in a synchronized rhythm.

Enter organoids. These structures loosely mimic their original counterparts in both their genes and diverse cell types. Grown inside lab dishes, the 3D blobs of tissue are widely used as surrogate organs to test new drugs or advance theories on how things work inside the body—for example, how to repair damage from a heart attack. But despite promising results in animals, the heart organoids can’t regenerate or repair native organs.

That is, until now. A new study published this month in Nature Biomedical Engineering linked digital electrical components with biological cells into a cyborg organoid that, when transplanted into animal models of heart failure, melded with and repaired living, beating hearts.