The liver rebuilds itself using mechanical forces

After liver injury, cells begin to divide to replace lost tissue. But that division also stops at the right moment. How the organ determines that stopping point has been an open question in biology. The researchers describe in Science how mechanical tension within the tissue plays a key role. Once enough cells have been produced, pressure within the tissue rises, and that physical signal dampens further cell division.

Tissue tension as a brake on cell growth

Cells sense their surroundings through receptors on their surface called mechanoreceptors. When tissue is full and tension is high, these signals alter the activity of growth-regulating genes. This process is called mechanotransduction: the conversion of a physical signal into a biological response. In liver regeneration, it acts as a built-in brake that prevents the organ from overgrowing.

The comparison with cancer is instructive: in tumours, this inhibitory mechanism is disrupted. Cells keep dividing even when space runs out. The liver demonstrates that healthy tissue depends on a precise interplay of pressure and signalling molecules to guide regeneration.

Relevance for liver disease and ageing

In chronic liver disease, such as that caused by prolonged inflammation or fatty liver, regenerative capacity becomes impaired. Tissue stiffens through fibrosis and loses elasticity. That could disrupt the mechanotransduction signal and stall repair. If so, restoring the mechanical properties of liver tissue might in principle support recovery.

The authors stress that the findings are based on animal models and cell studies. Whether the same mechanism governs human liver regeneration, and whether it can serve as a therapeutic target, requires further investigation.

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