Bile Acids Regenerate Livers

[Angel]

New research reveals regenerating liver tissue may depend on signals that indicate there is an imbalance in bile, specifically bile acids.

When the liver is injured, it can regrow. If doctors can understand how this happens, it could help them treat liver disease. Researchers from Baylor College of Medicine in Houston say bile acids provide key information about the state of the liver.

"[Bile acids] are released into the gut as part of digestion, reabsorbed and then back to the liver. More than 90 percent are cycled," says David Moore Ph.D., Baylor College of Medicine professor of molecular and cellular biology. "You do not get rid of the bile acids when you lose a piece of liver. Instead, you expose the remaining portion to a higher relative amount of bile acids, sending a signal through a specific receptor called FXR to activate liver regeneration."

Moore says it is difficult for animals bred to lack FXR to regenerate liver. When given a diet containing bile acids, the animals' livers regenerated faster.

People who take medications that sequester bile acids, such as cholesterol lowering drugs, cannot regenerate liver. Drugs could potentially be developed taking this finding into consideration, perhaps promoting the growth of liver.
The author concluded FXR and possibly other receptors maintain equilibrium in liver growth and function.