Magnetically-Actuated Dynamic Culture System for Investigating Mechanical Effects on Biological Growth

This study investigates the effects of mechanical stimulation on the growth and behavior of the slime mold Physarum polycephalum on a magnetic-field-driven dynamic substrate. The culture medium was designed to stretch and contract periodically, driven by an external magnetic field. The slime mold, which exhibits rhythmic contraction and expansion cycles in its protoplasm, was cultured on this dynamic substrate, with mechanical stimulation applied at frequencies of 60–100 s per cycle. Observations from time-lapse videos revealed periodic changes in the intensity of the slime mold’s network tubes, with significant effects on the flow and diameter of the tubes. These rhythmic mechanical stimuli influenced the slime mold’s growth rate, with results indicating that the applied stimulation enhanced the slime mold’s movement speed and growth. The findings suggest that mechanical stimuli, especially those closely matched to the organism’s natural rhythmic cycles, can significantly impact the growth and behavior of biological organisms. This work lays the groundwork for further studies on how mechanical stimuli can be harnessed to modulate biological processes in living systems.