Aspartate aminotransferase (AST/GOT) Assay Kits

Aspartate aminotransferase (AST) is an aminotransferase enzyme that catalyzes the conversion of L-aspartate and α-ketoglutarate into glutamate and oxaloacetate. It is also known as glutamic oxaloacetic transaminase (GOT). AST is highly abundant in the liver, myocardium, and skeletal muscle and is released into the bloodstream due to increased cell permeability or cell death. Therefore, it serves as a marker for organ damage, including liver injury.

In addition to AST, alanine aminotransferase (ALT) is commonly used as a marker for liver injury. ALT is predominantly found in the liver, making it a more specific marker for liver damage. In contrast, because AST is also present in the myocardium and skeletal muscle, an elevated AST level with normal or minimally elevated ALT may indicate cardiac or muscle injury. Furthermore, AST has a shorter half-life in the bloodstream compared to ALT, which allows for the assessment of disease status, including liver injury, based on this difference.

AST and ALT are also useful indicators of liver fibrosis caused by conditions such as metabolic dysfunction-associated steatotic liver disease (MASLD). Liver fibrosis scoring systems, including the NAFLD fibrosis score (NFS)¹⁾ and the Fibrosis-4 (FIB-4)²⁾ index, incorporate AST and ALT as key parameters.

Principle of the AST (GOT) assay

When a sample is mixed with Substrate-Enzyme Solution and α-KG Solution, glutamate and oxaloacetate are formed from L-aspartate and α-ketoglutarate in a reaction catalyzed by AST in the sample. The oxaloacetate thus produced is converted to malate by malate dehydrogenase (MDH). At the same time, NADH is oxidized to NAD, and the absorbance at 340 nm decreases. Finally, the reaction is stopped using a reaction Stop Solution, and the absorbance is measured to determine the AST activity value in the sample.

LabAssay™ AST (GOT) is a kit used for the determination of AST in blood (serum, plasma). With the use of a microplate, this kit provides a quick and convenient method for measuring AST in samples.

[Note] LabAssay™ series are reagents for research purposes. They cannot be used for diagnostic purposes.

Kit Performance

1. Angulo, P. et al.: Hepatology, 45(4), 846(2007).
   The NAFLD fibrosis score: a noninvasive system that identifies liver fibrosis in patients with NAFLD
2. Shah, A. G. et al.: Clin. Gastroenterol. Hepatol., 7(10), 1104(2009).
   Comparison of noninvasive markers of fibrosis in patients with nonalcoholic fatty liver disease