Planta Med 2011; 77 - WSII3
DOI: 10.1055/s-0031-1282102

Potential inhibitors of chikungunya and dengue viruses isolated from Malagasy plants

M Bourjot 1, P Leyssen 2, C Eydoux 3, J Guillemot 3, B Canard 3, P Rasoanaivo 4, F Guéritte 1, M Litaudon 1
  • 1Centre de Recherche de Gif, Institut de Chimie des Substances Naturelles (ICSN), CNRS, avenue de la terrasse, 91190 Gif sur Yvette, France
  • 2Rega Institute for Medical Research, Minderbroedersstraat, B3000, Leuven, Belgium
  • 3Laboratoire d'Architecture et de Fonction des Macromolécules Biologiques (AFMB), avenue de Luminy, 13288 Marseille, France
  • 4Institut Malgache de Recherches Appliquées (IMRA), 102 Antananarivo, B.P.3833, Madagascar

Chikungunya virus (CHIKV) and dengue virus (DENV) are two emerging arboviruses. CHIKV has recently re-emerged, causing massive epidemics that have moved from Africa throughout the Indian Ocean to India and Southeast Asia. In humans, it is responsible for an acute disease, characterized by a triad of fever, arthralgia and maculopapular rash. [1] Regarding the dengue fever, it affects more than 50 million people annually. [2] Increasing mortality and geographical expansion are the drastic changes noted in the recent epidemiology of the disease. No specific antiviral therapy is currently available, on the market, for these two diseases.

A screening on a cellular assay was performed on 400 plants from the Indian Ocean Islands. This screening has led to the selection of Flacourtia ramontchi L'Hér. (Salicaceae), a tree distributed in the south of Asia and in Madagascar. Fruits and seeds are used in folk medicine for the treatment of rheumatic arthralgia, cholera and dysentery. [3]

Eight new phenolic glycosides and one caffeic acid derivative, together with three known phenolic glycosides and one betulinic acid derivative were obtained by a bioassay-guided isolation from the stem bark. The phenolic glycosides have a salicin core structure; this core may be esterified with benzoic acid and/or 1-hydroxy-6-oxocyclohex-2-en-1-carboxylic acid, on the glucose moiety in 2', 3' and 4' positions and on the primary alcohol function of the salicyl alcohol moiety.

Promising results were obtained on the dengue RNA polymerase inhibition assay and preliminary structure-activity relationships were deduced. CHIKV assays are in progress.

Keywords: Flacourtia ramontchi, Salicaceae, phenolic glycosides, chikungunya, dengue, emerging viruses

Acknowledgement: This work was financially supported by Museum National d'Histoire Naturelle.

* PHYTOCHIK project was supported financially by CRVOI (Centre de Recherche et de Veille sur les maladies émergentes dans l'Océan Indien)

References: 1. Solignat et al. (2009) Virology 393: 183–197

2. Massé et al. (2010) Antiviral Res 86: 296–305

3. Chai X-Y et al. (2009) Planta Med 75: 1246–1252