The human body is a veritable cellular highway with up to 37 trillion cells traveling about and carrying out all essential life functions, from taking in nutrients and converting them to energy, to repairing a skinned knee. In large part, cells get their marching orders from electric fields influencing their functions.
In fact, new evidence from the University of Houston suggests that cells are incredibly sensitive to electrical fields, much more so than older scientific theories suggest.
“Our research challenges long-held assumptions about the limits of cellular electrical sensing and explains how cells detect electric fields with remarkable sensitivity,” reports Yashashree Kulkarni, Bill D. Cook Professor of Mechanical and Aerospace Engineering at UH in Proceedings of the National Academy of Sciences.
Kulkarni supervised the work of graduate student Anand Mathew, who led the research.
For decades, scientists thought cells couldn’t detect very weak electric fields because of “thermal noise” — tiny random movements caused by heat. It’s like trying to hear a whisper during a loud rock concert: the background noise drowns it out. Scientists believed this “noise floor” set the limit for what cells could possibly sense.
Kulkarni and Mathew’s study presents a compelling new explanation: active matter within the cell membrane can push the system out of equilibrium, enabling heightened electrical sensitivity.
“Biological membranes are not passive,” Kulkarni said. “They are embedded with active proteins and other components that continuously consume energy, creating dynamic, nonequilibrium environments. Our findings show that these active processes can fundamentally change the way cells respond to mechanical and electrical stimuli.”
The researchers created a new theoretical model using nonequilibrium statistical mechanics — a type of science that studies systems always using energy. The new model helps explain how electromechanical membranes in cells move and change in their active, energy-filled environment.
Their analysis shows that these energy-consuming processes can lead to a dramatic increase in electrical sensitivity - offering a theoretical model that aligns with experimental observations in many biological systems.
“Understanding how cells can actively respond to their environment could inform the development of next-generation medical devices, biosensors, and therapies for various diseases,” Mathew said. “By harnessing the concept of active matter, we can begin to design systems that mimic or even exceed the sensing capabilities found in nature.”
“I am truly grateful to have received the NSF BRITE Pivot award which has supported my group’s research in understanding the mechanics of active matter,” Kulkarni added.