Anti-Inflammatory Effect of Garcinol Extracted from Garcinia dulcis via Modulating NF-κB Signaling Pathway

Garcinia is a significant medicinal plant with many beneficial phytoconstituents, including garcinol. This study investigated the anti-inflammatory effect of garcinol isolated from Garcinia dulcis fruit in LPS-activated THP-1 and Raw 264.7 macrophages. The results demonstrated that the low concentration of garcinol did not alter cell viability. Furthermore, co-incubation of garcinol with LPS inhibited the production of pro-inflammatory cytokines, including TNF-alpha, IL-8, IL-6, IL-1 beta, and pro-inflammatory mediators, including iNOS and COX-2 at the mRNA and protein expression levels. Garcinol also decreased the secretion of TNF-alpha, IL-6, IL-1 beta, PGE2, and NO. Moreover, the anti-inflammatory effects involved an alteration in the NF-kappa B signaling pathway. Downregulation of pIKK alpha/beta, pI kappa B alpha, and pNF-kappa B was observed, hence reducing the translocation of pNF-kappa B from the cytosol into the nucleus, which subsequently decreased the production of pro-inflammatory molecules. Therefore, garcinol isolated from Garcinia dulcis is a potential candidate as an anti-inflammatory agent for inflammation-related disease treatment.