Liver enzymes

Liver enzymes are a group of enzymes found within the liver that play a crucial role in the liver's metabolic and detoxification functions. These enzymes facilitate various chemical reactions necessary for processing nutrients, breaking down drugs, and eliminating toxic substances from the body. The most commonly evaluated liver enzymes in clinical practice are Alanine transaminase (ALT), Aspartate transaminase (AST), Alkaline phosphatase (ALP), and Gamma-glutamyl transferase (GGT).

Functions

Liver enzymes are involved in a wide range of biological processes:

• ALT and AST: Primarily involved in the amino acid metabolism and are indicators of liver cell injury.
• ALP: Found in the liver, bone, kidney, and bile ducts, this enzyme is associated with bile formation and transport.
• GGT: Plays a role in the transfer of amino acids and peptides across the cellular membrane and is a marker for liver damage, especially due to alcohol consumption or bile duct obstruction.

Clinical Significance

Elevated levels of liver enzymes in the blood can indicate liver damage or inflammation. Conditions that may cause elevated liver enzyme levels include hepatitis, fatty liver disease, cirrhosis, and liver cancer. Medications, alcohol consumption, and certain herbal supplements can also elevate liver enzyme levels.

Diagnosis and Monitoring

The assessment of liver enzyme levels is typically done through a blood test, often part of a liver function test. Abnormal results may prompt further investigation to determine the underlying cause of liver dysfunction, including imaging studies and liver biopsy.

Treatment and Management

Treatment for elevated liver enzymes depends on the underlying cause. It may involve lifestyle changes, such as diet and exercise, reducing alcohol consumption, or changing medications that might be affecting liver health. In more severe cases, specific medical treatments or surgery may be required.

See Also

• Liver function tests
• Hepatotoxicity
• Liver disease
• Metabolism