aszpartátaminotransferáz

Aspartate aminotransferase, often abbreviated as AST, is an enzyme found in various tissues throughout the body, including the liver, heart, muscles, kidneys, and brain. It plays a crucial role in amino acid metabolism by catalyzing the transfer of an amino group from aspartate to alpha-ketoglutarate. This reaction is a key step in the malate-aspartate shuttle, which is important for cellular energy production.

In clinical settings, AST is primarily known as a biomarker for liver damage. When liver cells are injured or inflamed, AST is released into the bloodstream, leading to elevated levels in blood tests. Therefore, AST levels are often measured as part of a liver function test panel to assess the health of the liver and to help diagnose conditions such as hepatitis, cirrhosis, and fatty liver disease.

While the liver is a major source of AST, elevated levels can also indicate damage to other organs. For instance, significant elevations might suggest a heart attack, as AST is also found in cardiac muscle. Muscle injury, such as from strenuous exercise or trauma, can also contribute to higher AST levels. Because of its presence in multiple tissues, AST alone is not always specific for liver disease, and its interpretation in conjunction with other liver enzymes and clinical findings is essential for accurate diagnosis.