Aspirin exerts several beneficial effects within the vasculature that result in protection against intravascular inflammation and resultant atherosclerosis. These actions of aspirin involve, in part, its ability to modify the activity of lipid-synthetic enzymes. Which of the following enzymes is a target for aspirin-mediated modification resulting in an altered activity?

Question

Quizplus · Accepted Answer

Aspirin primarily targets and acetylates the enzyme cyclooxygenase (COX), specifically COX-1 and COX-2, leading to the inhibition of prostaglandin synthesis, which plays a role in inflammation and atherosclerosis. Aspirin-induced acetylation of COX-2 alters the enzyme such that it converts arachidonic acid to 15R-hydroxyeicosatetraenoic acid (15R-HETE) instead of into prostaglandin H2 (PGH₂). 15R-HETE is then rapidly metabolized to the epi-lipoxins in monocytes and leukocytes through the action of 5-lipoxygenase (5-LOX).

Aspirin Exerts Several Beneficial Effects Within the Vasculature That Result