A Microscopic Human Heart on a Chip


microscopic human heart

A Microscopic Human Heart on a Chip Credit:Anurag Mathur/Healy Lab

An innovative aid in medical science: A microscopic human heart on a chip. Researchers construct a heart-on-a-chip device in order to quickly and efficiently test how heart muscle responds to pharmaceuticals. Yay science.

To test the efficacy of a drug the common route is to start testing on cells in a suspension and then move on to animal testing ranging from fruit flies to monkeys. These tests not only provide valuable safety data on a potential drug, they also demonstrate effectiveness of a drug in a living creature. One problem with this approach is that animal trials take time, and the results aren’t always directly applicable to people since there are differences between animals and people. New research from University of California – Berkeley have found a way to reduce the number of animal trials by making a device containing a human hearts on a chip.

A Microscopic Human Heart on a Chip

The research published March 9th, in the journal Scientific reports, describe how this tiny heart functions.

Animal testing is an invaluable tool for researchers as it allows them to predict success or failure of a drug before it’s put to use in people. The problem is that though animals are similar to people they’re not identical. In the case of the heart, different animals have varying number of ion channels, a difference that can greatly change the efficacy of drugs targeting the heart.

In this study researchers might have found a way to avoid the issues faced by animal testing by designing a new system to test drugs, a heart-on-a-chip made from stem cells. These mini-hearts are made by changing human adult stem cells (iPSCs) into heart cells. The connective tissue and heart cells, making up a normal human heart, are placed in a 3D confinement and spaced to form tissue similar to the human heart. To simulate blood vessels, microfluidic channels on either side of the cell area exchanged nutrients and drugs with the human heart tissue.

Within 24 hours of being loaded onto the chip the human heart cells begins to beat at a normal pace of between 55 and 80 beats per minute.

To see if their designed heart responded in the same way as a normal human heart would, researchers tested four well-known drugs that affect heart function: isoproterenol, E-4031, verapamil and metoprolol. By monitoring changes in heart rate of the heart on a chip researchers could gauge if the drugs had any effect.

Exposure to isoproterenol, a drug used to treat bradychardia (slow heart rate), intensified the beating of the heart-on-a-chip to 55-124 beats per minute. The other drugs tested in the study are used to reduce the heart rate, these also proved successful, reducing the heart rate of the heart on a chip device.

Placing a microscopic human heart on a chip could reduce development time of new drugs takes and have the potential to replace some of the animal testing needed to determine safety and efficacy of new drugs.

“Ultimately, these chips could replace the use of animals to screen drugs for safety and efficacy,” said research leader Kevin Healy.