‘Biohybrid’ fish built to test synthetic heart cells (VIDEO)

Researchers from Harvard and Emory universities in the US have crafted a bionic fish out of two sets of lab-grown heart muscle cells, one set for each side of its flexible tail. When one set of cells contracts, the tail is pulled in one direction, and vice versa for the other set of cells, triggered by the opening of “mechanosensitive protein channels” and a pacemaker-like device that regulates the speed of the contractions.

A video posted to one of Harvard’s YouTube channels on Wednesday shows the “fully autonomous biohybrid fish” in action. The accompanying text explains that engineering tiny fishbots was not an end in itself, but a proof of concept for the next step in eventually developing an artificial human heart.

Equipped with only the most basic equipment, the miniature devices – whose movements were inspired by the zebrafish species – were able to swim for over 100 days and actually got better at the motions the longer they swam, the developers said. Researchers noted that, by the end of the device’s life span, it was moving at a speed similar to that of a real (not bionic) zebrafish.

The team, whose research has been published in the journal Science, said the success of their fish experiment brings them a step further in developing a far more complex artificial heart, and allows researchers to study the mechanics of heart conditions like arrhythmia while they work on building longer-lasting models.