生物活性

• 描述Salicylic acid is an effective inhibitor of COX-2 activity at concentrations far below those required to inhibit NF-κB (20 mg/mL) activation. Salicylic acid inhibits prostaglandin E2 release when add together with interleukin 1β for 24 hr with an IC50 value of 5 μg/mL, an effect that is independent of NF-κB activation or COX-2 transcription or translation. Salicylic acid acutely (30 min) also causes a concentration-dependent inhibition of COX-2 activity measured in the presence of 0, 1, or 10 μM exogenous arachidonic acid. In contrast, when exogenous arachidonic acid is increased to 30 μM, salicylic acid is a very weak inhibitor of COX-2 activity with an IC50 of >100 μg/mL. Salicylic acid causes a concentration-dependent inhibition of COX-2 activity in the absence of added arachidonic acid or in the presence of 1 or 10 μM exogenous substrate with an apparent IC50 value of approximately 5 μg/mL. However, when the same experiments are performed using 30 μM arachidonic acid, salicylic acid is an ineffective inhibitor of COX-2 activity, with an apparent IC50 value of more than 100 μg/mL, and achieves a maximal inhibition of less than 50%^[3]. Salicylic acid (SA) is a key plant hormone that mediates host responses against microbial pathogens^[4].