Anti-nociceptive property of thymol: animal study with molecular docking and MD simulation studies

Nociceptive pain is a physiological response to tissue injury that activates peripheral and central pain pathways. Thymol (THY) has been reported to possess various pharmacological activities, including potential analgesic effects. In this study, we investigated the anti-nociceptive activity of THY and explored its possible interaction with cyclooxygenase (COX) enzymes using both in vivo and in silico approaches. 60 Swiss albino mice were randomly divided into experimental groups (n = 5 per group) and administered THY orally at doses of 15, 30, and 60 mg/kg. The anti-nociceptive effects were evaluated using the acetic acid-induced writhing test and the hot plate test. Diclofenac sodium (Di-Na) (10 mg/kg) was used as the standard reference drug, while distilled water served as the vehicle control. In addition, molecular docking studies were performed to predict the binding affinity of THY and diclofenac sodium toward COX-1 and COX-2 enzymes, and ligand-receptor interactions were visualized using computational tools. The results demonstrated that THY produced a dose-dependent reduction in nociceptive responses in both experimental models compared to the control group. In silico analysis showed that THY exhibited binding affinities of - 6.3 kcal/mol with COX-1 and COX-2, forming hydrogen bond interactions with the binding site of both enzymes. MD simulation results indicated that the THY-COX complexes remained stable throughout the simulation period, supporting the plausibility of these predicted interactions. Overall, THY showed significant anti-nociceptive activity in vivo, while computational results suggest potential interaction with COX enzymes. However, further biochemical and mechanistic studies are required to confirm its exact mode of action.