In Vivo and in Vitro Anti-Inflammatory Activity of Neorogioltriol, a New Diterpene Extracted from the Red Algae Laurencia glandulifera

• Main Authors: Riadh Kharrat, Safa Tarhouni, Lamia Guizani-Tabbane, Vassilios Roussis, Constantinos Vagias, Sameh Rabhi, Maria Kladi, Rim Chatter, Rym Ben Othman
• Format: Article
• Language: English
• Published: MDPI AG 2011-07-01
• Series: Marine Drugs
• Subjects: anti-inflammatory; neorogioltriol; Laurencia; TNFα; NF-κB; NO; COX-2; carrageenan
• Online Access: http://www.mdpi.com/1660-3397/9/7/1293/

Neorogioltriol is a tricyclic brominated diterpenoid isolated from the organic extract of the red algae Laurencia glandulifera. In the present study, the anti-inflammatory effects of neorogioltriol were evaluated both in vivo using carrageenan-induced paw edema and in vitro on lipopolysaccharide (LPS)-treated Raw264.7 macrophages. The in vivo study demonstrated that the administration of 1 mg/kg of neorogioltriol resulted in the significant reduction of carregeenan-induced rat edema. In vitro, our results show that neorogioltriol treatment decreased the luciferase activity in LPS-stimulated Raw264.7 cells, stably transfected with the NF-κB-dependent luciferase reporter. This effect on NF-κB activation is not mediated through MAPK pathways. The inhibition of NF-κB activity correlates with decreased levels of LPS-induced tumor necrosis factor-alpha (TNFα) present in neorogioltriol treated supernatant cell culture. Further analyses indicated that this product also significantly inhibited the release of nitric oxide and the expression of cyclooxygenase-2 (COX-2) in LPS-stimulated Raw264.7 cells. These latter effects could only be observed for neorogioltriol concentrations below 62.5 µM. To our knowledge, this is the first report describing a molecule derived from Laurencia glandulifera with anti-inflammatory activity both in vivo and in vitro. The effect demonstrated in vitro may be explained by the inhibition of the LPS-induced NF-κB activation and TNFα production. NO release and COX-2 expression may reinforce this effect.