Cells Use ‘Bioelectricity’ To Coordinate and Make Group Decisions

Amazing stuff!

"... According to the new results, as epithelial tissue grows, cells are packed more tightly together, which increases the electrical current flowing through each cell’s membrane. A weak, old, or energy-starved cell will struggle to compensate, triggering a response that sends water rushing out of the cell, shriveling it up and marking it for death. In this way, electricity acts like a health checkup for the tissue and guides the pruning process. ...

The new discovery adds to the growing assortment of bioelectrical phenomena that scientists have discovered playing out beyond the nervous system, from bacteria swapping signals within a biofilm to cells following electric fields during embryonic development. Electricity increasingly appears to be one of biology’s go-to tools for coordinating and exchanging information between all kinds of cells. ..."

From the abstract:

"Epithelial cells work collectively to provide a protective barrier, yet they turn over rapidly through cell division and death. If the numbers of dividing and dying cells do not match, the barrier can vanish, or tumours can form. Mechanical forces through the stretch-activated ion channel Piezo1 link both of the processes; stretch promotes cell division, whereas crowding triggers live cells to extrude and then die. However, it was not clear what selects a given crowded cell for extrusion.

Here we show that the crowded cells with the least energy and membrane potential are selected for extrusion.

Crowding triggers sodium (Na+) entry through the epithelial Na+ channel (ENaC), which depolarizes cells. While those with sufficient energy repolarize, those with limited ATP remain depolarized, which, in turn, triggers water egress through the voltage-gated potassium (K+) channels Kv1.1 and Kv1.2 and the chloride (Cl−) channel SWELL1.

Transient water loss causes cell shrinkage, amplifying crowding to activate crowding-induced live cell extrusion.

Thus, our findings suggest that ENaC acts as a tension sensor that probes for cells with the least energy to extrude and die, possibly damping inadvertent crowding activation of Piezo1 in background cells.

We reveal crowding-sensing mechanisms upstream of Piezo1 that highlight water regulation and ion channels as key regulators of epithelial cell turnover."

Cells Use ‘Bioelectricity’ To Coordinate and Make Group Decisions | Quanta Magazine "The discovery that tissues use electricity to expel unhealthy cells is part of a surge of renewed interest in the currents flowing through our bodies."

Energy deficiency selects crowded live epithelial cells for extrusion (open access)

A cell shrinks, due to a change in its bioelectrical properties, before it is extruded from tissue. The “lightning” flash represents a change in light refraction as the membrane is depolarized and water exits the cell. Original video(opens a new tab) quality enhanced using AI with creator’s approval. (Images taken every two minutes.)