Hepatocyte is the main working cell of the liver. Hepatocytes make up about 80% of the organ's mass and handle almost all of its "chemistry": synthesis of blood proteins, formation of bile, detoxification of toxins and ammonia, and regulation of glucose and fat metabolism. When the cells are damaged, the enzymes ALT and AST leak from them into the blood — which is why these tests serve as a marker of the liver's condition.
What the hepatocyte does
The hepatocyte is a universal biochemical factory. It synthesizes albumin, fibrinogen and most clotting factors, as well as transport proteins and lipoproteins. In it, gluconeogenesis takes place — the formation of glucose from amino acids and glycerol — along with the synthesis of cholesterol and bile acids.
Another key task is detoxification: the hepatocyte converts toxic ammonia into urea, processes drugs and metabolic products, and forms bilirubin as part of bile. Impaired bile flow is called cholestasis. All this energy-intensive work is powered by the cell's numerous mitochondria.
Damage: cytolysis, ALT and AST
Normally ALT and AST are inside the hepatocyte. When the cell membrane is damaged (virus, alcohol, drugs, fat overload), the enzymes "leak" into the blood — this is a laboratory sign of cytolysis. ALT is more specific to the liver, whereas AST is also present in the heart and muscles, so they are assessed together, often adding GGT. Importantly, the degree of enzyme rise does not always reflect the extent of damage — the result is read in context.
From cell death to fibrosis and cirrhosis
The death of a few hepatocytes is not dangerous: the liver recovers well. But with chronic injury — for example, in fatty liver disease with steatosis — scar tissue is deposited in place of the dead cells. This is how liver fibrosis develops, whose stages are graded on the METAVIR scale, and whose severity is indirectly reflected by liver stiffness. The extreme stage is cirrhosis, when the normal architecture of the organ is irreversibly remodeled.
Regeneration
The liver is unique in its capacity for recovery: after part of the organ is removed, it can regrow its mass almost to the original even in old age. A substantial fraction of hepatocytes is renewed over a lifetime, and some cells become polyploid (with a doubled set of chromosomes). However, regeneration is not limitless: if the damaging factor acts constantly, scarring gains the upper hand over recovery.
Calculate using this marker
Calculators where Hepatocyte is used directly:
Frequently asked questions
Do hepatocytes regenerate?
Yes, the liver has a high capacity for regeneration — it can restore its mass even after surgery to remove part of the organ. But with constant damage, the dead cells are replaced by scar (fibrosis), and this tissue no longer turns back into working hepatocytes.
Why do ALT and AST rise in liver disease?
These enzymes are normally inside the hepatocytes. When the cell membrane is damaged, they enter the blood. ALT is more specific to the liver, while AST is also found in the heart and muscles, so the values are interpreted together.