Biologists demonstrated an optical stimulator of the heart on flies

Biologists managed to create an optogenetic stimulator of the heart that affects heart contractions with laser pulses. The description of a successful experiment conducted on Drosophila flies appeared this week in the journal Science Advances.

Classic cardiac stimulants work by sending electrical impulses to the cells of an organ. Under the influence of impulses, the cells contract, and thus a constant rhythm of the heartbeat is maintained. In this experiment, scientists used the achievements of a relatively new field of science, optogenetics .

In optogenetics, to stimulate cells (primarily biologists dealt with neurons), they are genetically modified, forcing cells to produce special proteins - ion channels that allow ions to travel through the cell membrane. Due to the presence of these proteins, cells begin to respond to light.

At the very beginning of the development of optogenetics, experimental animals had to introduce fiber into the body in order to supply light pulses to the region of interest. This year, American scientists have developed wireless microscopic implants equipped with a radio module and LED. They are able to turn on and off by external control.

In our experiment, such tricks were not required. Drosophila flies were genetically prepared for their heart to respond to light, and stimulation was carried out by laser pulses that penetrated through the exoskeleton on the fly’s abdomen. In the course of the experiment, it was found that when laser pulses were applied at a frequency of 10 Hz, puffed hearts beat in full accordance with the supplied pulses.


In the video, the heart beats flies both independently and under the influence of laser pulses

Chao Zhou [ of Chao of Zhou ], an assistant professor of bioengineering at the University of Lihayskogo, who led the work, says that optical pacemakers there are a number of advantages over traditional. For example, an optical stimulator does not need to be implanted. It acts only on a specific set of cells, while electrical can affect the surrounding tissue.

Similar studies have already been successfully carried out on other favorite creatures of biologists - zebrafish and mice. However, in the case of fish, exposure was possible only at the stage of embryo, and in mice, when the chest was opened. In this case, non-invasive stimulation was demonstrated in the laboratory.


The American researcher Seymour Benzer holds the Drosophila model.

Since in the case of Drosophila flies it is possible to influence them at all stages of development, this allows scientists to test interesting hypotheses. For example, by studying specially bred flies with a predisposition to heart attacks, it can be determined whether pacing of the developing embryo will affect the improvement of the heartbeat situation in adult flies.

Of course, such a technology has not yet been adapted for human experiments. You will either have to continue to implant the stimulator surgically, or develop a system in which cells will respond to radiation in the near infrared part of the spectrum (capable of penetrating through tissues). True, for this it will be necessary to figure out how to focus this radiation so that it does not scatter in the tissues. But Zhou is sure that there is nothing impossible.


The world's first implantable pacemaker from Siemens Elema.

Pacemakers first began to be used in the 1950s. The first prototype was located outside the body, and received power through the wires.