Interplay of damage and repair in the control of epithelial tissue integrity in response to cyclic loading

TL;DR

This paper reviews how epithelial tissues respond to cyclic stretching, emphasizing the importance of timescales in damage accumulation and repair, which is crucial for understanding tissue homeostasis and resilience.

Contribution

It provides a comprehensive analysis of the timescales involved in cyclic loading, damage, and repair mechanisms in epithelial tissues, highlighting differences from synthetic materials.

Findings

Damage can be reversed by repair mechanisms within shorter timescales than cyclic loading.

Timescales are critical for understanding tissue resilience and homeostasis.

Biological tissues exhibit unique fatigue behaviors compared to synthetic materials.

Abstract

Epithelial tissues are continuously exposed to cyclic stretch. Physiological stretching has been found to regulate soft tissue function at the molecular, cellular, and tissue scales, allowing tissues to preserve their homeostasis and adapt to challenges. In contrast, dysregulated or pathological stretching can induce damage and tissue fragilisation. Many mechanisms have been described for the repair of epithelial tissues across a range of time-scales. In this review, we present the timescales of (i) physiological cyclic loading regimes, (ii) strain-regulated remodelling and damage accumulation, and (iii) repair mechanisms in epithelial tissues. We discuss how fatigue in biological tissues differs from synthetic materials, in that damage can be partially or fully reversed by repair mechanisms acting on timescales shorter than cyclic loading. We highlight that timescales are critical to understanding the interplay between damage and repair in tissues that experience cyclic loading, opening up new avenues for exploring soft tissue homeostasis.