Library · Physiology
Liver Regeneration
Make it clearer
If two thirds of the liver is removed in surgery, what is left grows back until it regains essentially 100% of its original size.
It is worth understanding how, because it is not what you would imagine. The cells left behind multiply from within. It is like a town that rebuilds its population without anyone moving in, because the people who stayed have children. The work is done by hepatocytes, the liver's main cells, which make up as much as 80% of its cell mass. Normally they sit idle; after the loss they exit that quiescence, run through the cell cycle, the full sequence that leads a cell to divide, and when they finish they return to their resting state, called G0.
One thing is just as important as starting: knowing when to stop. Once the lobule, the unit the liver is built from, has been reconstituted, multiplication has to halt. The best studied brake is a molecule called TGF-beta.
And this capacity is not unlimited. If regeneration is disrupted after a chemical injury, a viral infection or chronic inflammation, it can end in fulminant hepatic failure, meaning the liver stops working all at once.
In brief
After two thirds of the liver is removed, the tissue grows back to essentially 100% of its original size.
Hepatocytes, up to 80% of the liver's cell mass, exit quiescence, run through the cell cycle and return to G0.
The cells left behind multiply until the liver is back to its full size.
Once the lobule is reconstituted, proliferation has to stop; the best studied brake is TGF-beta.
Disrupted regeneration after certain chemical injuries, viral infections or chronic inflammation can end in fulminant hepatic failure.
Sources (1)
- Seminars in Cell and Developmental Biology, via PubMed CentralCellular and molecular basis of liver regenerationPublished
This page explains the topic in general terms; it does not tell anyone what treatment to follow.
Updated