Molecular Docking Prediction and in Vitro Studies Elucidate Anti-inflammatory Effect of Garcinia Extract Against Inducible Nitric Oxide Synthase and Cyclooxygenase-2 Targets

Garcinia is a tropical plant that has been traditionally used in medicinal folklore for its potential antioxidant, antibacterial, anti-hyperlipidemic, anti-diabetic, hepatoprotective, etc. In this study, Garcinia herbal extract (GHE) and one of its important phytocompound (garcinol) were evaluated for their inhibitory action against important inflammatory markers inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) in lipopolysaccharide (LPS)-induced RAW 264.7 cells. iNOS and COX-2 plays an major role in the process of inflammation and inhibition of these molecules will help to alleviate the inflammatory process. The cells were pre-treated with two doses of Garcinia (230µg/ml and 115µg/ml); garcinol (12µM and 6µM) followed by stimulation with 1µg/ml of LPS for 24h. The results of the study demonstrated that GHE and garcinol plays an important role in suppressing LPS- induced relative mRNA expression of iNOS, COX-2 and subsequent reduction in the levels of nitric oxide and prostaglandin E 2 . Molecular docking analysis of garcinol and hydroxycitric acid, the major active components of GHE with iNOS and COX-2 proteins showed potent interaction with low binding energies. This study suggests that GHE (containing high percentage of HCA) and garcinol may possess anti-inflammatory activity thus providing a possibility for drug designing as iNOS and COX-2 inhibitors.