Investigation of the antinociceptive and antiinflammatory effects of syringic acid

In this thesis study, it was planned to investigate the antinociceptive and antiinflammatory effects of syringic acid. The antinociceptive effect of syringic acid was investigated by tail clip, tail immersion, hot plate, acetic acid-induced writhing and formalin tests. The antiinflammatory activity of this phenolic compound was examined by carrageenan-induced inflammation test. The locomotor activities of the mice were also evaluated by the activitymeter test. In the activitymeter test, syringic acid administered at doses of 50 and 100 mg.kg-1 did not change the ambulatory activities, horizontal and vertical movement numbers and walking distance of the mice. Syringic acid administrated at doses of 50 and 100 mg.kg-1 did not cause any change in reaction times, maximum possible effect % (MPE%) and area under the curve (AUC) values of mice in tail clip, tail immersion and hot plate tests. On the other hand, it reduced the number of writhing behaviors in the acetic acid-induced writhing test and shortened the paw licking times of the mice only in the second phase of the formalin test. These findings revealed that syringic acid possess a peripheral antinociceptive effect. Syringic acid showed anti-inflammatory effect by significantly reducing paw edema of rats in the carrageenan-induced inflammation test. In silico studies were performed to investigate interactions of syringic acid with cyclooxygenase (COX) and lipoxygenase (LOX) enzymes, which are closely related to analgesia and inflammation processes. The molecular docking and molecular dynamic simulation studies indicated that syringic acid successfully docked with COX-2 and 5-LOX enzymes and showed high affinity and continuous interactions with them.