In vitro acetylation of plasma proteins, enzymes and DNA by aspirin

HUMAN serum albumin (HSA) is permanently altered after exposure to therapeutic concentrations of acetylsalicylic acid (ASA, aspirin) either in vitro or in vivo1-3. Recently we showed that this structural alteration was the result of the acetylation of the HSA molecule by aspirin4,5. Because the acetylation of HSA by aspirin could occur by aminolysis resulting in an N-acetyl-HSA derivative, we decided to determine whether aspirin could acetylate other biological materials. We now report that aspirin acetylates a variety of body constituents in vitro.