Gigantol Isolated from the Whole Plants ofCymbidium goeringiiInhibits the LPS-Induced iNOS and COX-2 Expression via NF-κB Inactivation in RAW 264.7 Macrophages Cells

Abstract

During our efforts to find bioactive natural products with anti-inflammatory activity, we isolated gigantol from the whole plants of Cymbidium goeringii (Orchidaceae) by activity-guided chromatographic fractionation. Gigantol was found to have potent inhibitory effects on LPS-induced nitric oxide (NO) and prostaglandin E (2) (PGE (2)) production in RAW 264.7 cells. Consistent with these findings, gigantol suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) at the protein and mRNA levels in RAW 264.7 cells in a concentration-dependent manner. Our data also indicate that gigantol is a potent inhibitor of tumor necrosis factor-alpha (TNF-alpha), interleukin-1beta (IL-1beta) and interleukin-6 (IL-6) release and influenced the mRNA expression levels of these cytokines in a dose-dependent manner. Furthermore, a reporter gene assay for nuclear factor kappa B (NF-kappaB) and an electromobility shift assay (EMSA) demonstrated that gigantol effectively inhibited the activation of NF-kappaB, which is necessary for the expression of iNOS, COX-2, TNF-alpha, IL-1beta and IL-6. Thus, our studies suggest that gigantol inhibits LPS-induced iNOS and COX-2 expression by blocking NF- kappaB activation.

Antioxidant Biomarkers from Vanda coerulea Stems Reduce Irradiated HaCaT PGE-2 Production as a Result of COX-2 Inhibition

“…No concentration-dependent inhibitory effect was observed to allow IC 50 calculation for gigantol ( 3 ) effect on PGE-2 production. Wong JH et al also demonstrated that this compound ( 3 ) was able to reduce NF-κB expression on murine macrophages RAW 264.7 [38]. Thus, this transcriptor factor could be another target, leading to a reduction of PGE-2 synthesis and to a global anti-inflammatory effect on irradiated HaCaT.…”

Anti-inflammatory and anti-cancer activity of mulberry (Morus alba L.) root bark

“…There are growing evidences that several agents inhibiting NO production have been shown to suppress NF-κB activation [34-37]. NF-κB regulates expression of various genes associated with apoptosis, proliferation, cancer progression and inflammation [38].…”

Medicinal orchids and their uses: Tissue culture a potential alternative for conservation

“…They have been used variously in different diseases as anti rheumatic, antiinflammatory, antiviral, anti carcinogenic, anticonvulsive, diuretic, neuroprotective, relaxation, anti-aging, wound healing, hypoglycemic, antitumor and anticancer, antimicrobial, antiviral and many other activities (Ghanaksh and Kaushik, 1999;Shyur et al, 2004;Li et al, 2001;Shimura et al, 2007;Wang et al, 2006;Prasad and Achari, 1966;Kumar et al, 2000;Zhao et al, 2003;Satish et al, 2003;Watanabe et al, 2007, Won et al, 2006Lawler and Slaytor, 1970;Balzarini et al, 1992;Nayak et al, 2005;Miyazawa et al, 1999). For drugs derived from orchids, some novel discoveries, both in phytochemical and pharmacological properties, were reported by some researcher.…”