BPS2026 – Repetitive mechanical forces in piconewton scale enhanced mitochondrial stress and actin filament assembly in glioblastoma cell

Piconewton (pN)-level forces generated by molecular motors such as myosin are fundamental to cellular mechanics. These forces presented at molecular level are repetitive application; however, the influence of repetitive minute mechanical signals on cellular physiology remains largely unexplored. Herein, we applied mechanical forces (∼11.5 ± 2.0 pN) using magnetic tweezers on U87 glioma cells, and noticed reactive oxygen species (ROS) increased 1.5-2-fold following single pulse application but reverse effect was shown with repetitive stimulation. Moreover, mitochondrial oxidative stress increased 6-fold under repetitive force application, indicating the profound impact on mitoROS homeostasis. Subsequently, intracellular Ca 2+ increased 10-fold compared to single pulses, suggesting a Ca 2+ -ROS pathways. Notably, repetitive forces sustained Ca 2+ oscillations even when Piezo1, a major mechanosensitive Ca 2+ channel, was pharmacologically blocked. Furthermore, repetitive forces induced 3-fold increased F-actin formation versus 1.5-fold from single pulses under identical stimulation duration, suggesting the importance of repetitive forces stimuli. Collectively, these results reveal that repetitive pN-level forces distinctly activate mitochondrial ROS responses and enhanced Ca 2+ oscillations, subsequently promoting cytoskeletal assembly in glioblastoma cells. This study provides alternative insights into how repetitive minute mechanical signals regulate cellular morphological remodeling, emphasizing the critical importance of repetitive force stimulus in mechanotransduction.