Alpha-1 acid glycoprotein

Alpha-1 acid glycoprotein (AAG) is a protein that is produced primarily in the liver and secreted into the bloodstream. It is also known as orosomucoid (ORM) or acute phase protein due to its increased production during inflammation or infection.

Structure

Alpha-1 acid glycoprotein is a single-chain polypeptide consisting of 183 amino acids and has a molecular weight of approximately 41-43 kDa. It is heavily glycosylated, with about 45% of its mass consisting of carbohydrate chains. The protein has five N-linked glycosylation sites, which are occupied by complex oligosaccharide chains.

Function

The primary function of alpha-1 acid glycoprotein is not fully understood. However, it is known to have several important roles in the body. It acts as a transport protein, binding to various substances in the blood, including certain drugs, hormones, and lipids. This binding can affect the distribution and elimination of these substances in the body. Alpha-1 acid glycoprotein also has anti-inflammatory properties and can modulate the immune response.

Clinical significance

Levels of alpha-1 acid glycoprotein can increase in response to acute phase reactions, such as inflammation or infection. This makes it a useful biomarker for these conditions. Additionally, because of its role in drug binding, changes in alpha-1 acid glycoprotein levels can affect the pharmacokinetics of certain drugs, potentially influencing their efficacy and toxicity.

See also

• Acute phase protein
• Glycoprotein
• Liver