Moving muscle fibers with magnets ‘programs’ how they align within tissue

“The flexibility to make aligned muscle in a lab setting implies that we are able to develop mannequin tissues for understanding muscle in wholesome and diseased states and for growing and testing new therapies that fight muscle damage or illness,” says senior creator Ritu Raman, an MIT engineer. A greater understanding of the foundations that govern muscle progress may even have functions in robotics, she provides.

In a earlier investigation, Raman and colleagues discovered that “exercising” muscle fibers by making them contract in response to electrical stimulation for half-hour a day over the course of 10 days made the fibers stronger. This time, the researchers needed to discover whether or not mechanically stimulating the muscle fibers over the identical timeframe (fairly than letting them reply on their very own) would have the identical outcome. To analyze, they developed a way to mechanically stimulate muscle tissue that differs from typical lab methods.

“Usually, when folks need to mechanically stimulate tissues in a lab atmosphere, they grasp the tissue at each ends and transfer it forwards and backwards, stretching and compressing the entire tissue,” mentioned Raman. “However this does not actually mimic how cells speak to one another in our our bodies. We needed to spatially management the forces between cells inside a tissue, matching native techniques.”

To stimulate the muscle cells in a extra true-to-life means, Raman and her group grew cells in a Petri dish on a mushy gel that contained magnetic particles. Once they would transfer a magnet forwards and backwards below the gel, the particles moved forwards and backwards, too, which “flexed” the cells. The researchers may exactly management the way in which the gel moved, and, in flip, the magnitude and route of the forces the cells inside skilled, by altering the power and orientation of the magnet. To measure the alignment of the muscle fibers throughout the tissues and whether or not they contracted in synchrony, the group’s collaborators at Boston College developed a customized software program that routinely tracked movies of the muscle and generated graphs of its motion.

“We have been very stunned by the findings of our research,” mentioned Raman. Whereas mechanically stimulating the muscle fibers over the 10-day interval didn’t appear to make them any stronger, it did trigger all of them to develop in the identical route.

“Moreover, we have been excited to seek out that, once we triggered muscle contraction, aligned muscle was beating synchronously, whereas non-aligned muscle was not beating rhythmically,” mentioned Raman. “This confirmed our understanding that the shape and performance of muscle are intrinsically related, and that controlling type may also help us management operate.”

Raman and colleagues plan to take the research additional by investigating how totally different mechanical stimulation regimens affect each wholesome and diseased muscle fibers. Moreover, they plan to review how mechanical stimulation impacts different forms of cells.