Researchers use LED green light to activate genes to control insulin secretion

Many modern fitness trackers and smart watches are integrated with LEDs. Their green light, whether continuous or pulsed, can penetrate the skin and can be used to measure the wearer's heart rate during sports activities or rest. These watches have become very popular. A research team now wants to take advantage of the epidemic, using LEDs on the skin to control genes and change cell behavior.

The team is led by Martin fussenegger of the Department of biosystems science and Engineering in Basel. Explaining the challenge of this work, he said that there is no naturally occurring molecular system in human cells that responds to green light, so we have to build something new.

The researchers eventually developed a molecular switch that, once implanted, can be activated by the green light of a smart watch. The switch is linked to a gene network that researchers have introduced into human cells. Conventionally, they used HEK 293 cells as prototypes. According to the genes it contains, as long as the cell is exposed to green light, it can produce insulin or other substances. Turning off the light deactivates the switch and stops the process.

Because they use standard smart watch software, there is no need for researchers to develop special programs. In their tests, they turned on the green light by starting a running application. The new model will emit light pulses, which is even more suitable for keeping the gene network running. However, molecular switches are more complex. A molecular complex is integrated into the membrane of the cell and connected to a connector, similar to that of a railroad car. Once green light is emitted, the components projected into the cell are detached and transported to the nucleus, where a gene that produces insulin is triggered. When the green light goes out, the separated part is reconnected with the corresponding part embedded in the membrane.

The researchers tested their system on pig skins and living mice, implanted the right cells into the mice and strapped a smart watch like a backpack. Turning on the watch's running program, the researchers turned on the green light to activate the cascade. However, the researchers say the technology seems unlikely to enter clinical practice for at least a decade. The cells used in this prototype will have to be replaced by the user's own cells. In addition, the system has to go through the clinical stage before it can be approved, which means there are major regulatory barriers. So far, only a few cell therapies have been approved.