Excitable dynamics driven by mechanical feedback in biological tissues

TL;DR

This paper presents a theoretical framework explaining how mechanical feedback mechanisms in tissues can generate pulsatile activity patterns, including waves and pulses, influenced by cell geometry and response times.

Contribution

It introduces a simple mechanical feedback model at the cellular level that accounts for tissue-wide pulsatile activity and elucidates the role of cell packing geometry in tissue excitability.

Findings

Mechanical feedback can produce pulsatile activity in tissues.

Transition between pulses and waves depends on cellular response times.

Cell packing geometry influences tissue excitability.

Abstract

Pulsatory activity patterns, driven by mechanochemical feedback, are prevalent in many biological systems. Here we present a theoretical framework to elucidate the mechanical origin and regulation of pulsatile activity patterns within multicellular tissues. We show that a simple mechanical feedback at the level of individual cells - activation of contractility upon stretch and subsequent inactivation upon turnover of active elements - is sufficient to explain the emergence of quiescent states, long-range wave propagation, and traveling activity pulse at the tissue-level. We find that the transition between a propagating pulse and a wave is driven by the competition between timescales associated with cellular mechanical response and geometrical disorder in the tissue. This sheds light on the fundamental role of cell packing geometry on tissue excitability and spatial propagation of activity patterns.