Metabolomic study and pharmacological valorisation of species of the genus Psiadia endemic to Reunion and Mauritius islands.

16 species

76 crude extracts

⇢  Anticancer (HeLa cancer cell lines) ⇢  Antiplasmodial (Plasmodium falciparum) ⇢  Anti-inflammatory (Horseradish peroxydase)

SpeciesAnticancer

activity (IC50 µg/mL)

Antiplasmodial activity

(IC50 µg/mL)

Anti-inflammatory activity

(IC50 µg/mL) P. amygdalina (R) inactive 8,8 - 31,1 47,6 - inactive

P. anchusifolia (R) inactive 5,0 - 43,3 inactive

P. arguta (M) 22,8 - 36,1 11,2 - 22,4 inactive

P. dentata (R) 11,6 - 48,3 8,4 - 34,3 2,3 - 25,2

P. lithospermifolia (M) inactive 13,9 - 18,8 inactive(M) Endemic to Mauritius; (R) Endemic to La Réunion

Most active species :

The aim of this biological screening is to identify the most active species for anticancer, antiplasmodial and anti-inflammatory activities. Plants have been harvested from different locations and through two seasons (summer and winter) with the goal of analysing the geographical and seasonal variabilities of the chemical composition and thus, the biological activities.

⇢  Several locations Study of the geographical variability ⇢  Two seasons Study of seasonal variability

ASE extraction solvent AcOEt

In order to identify factors influencing the production of bioactives compounds, P. arguta have been multiplicated using in vitro culture techniques and micropropagated plants were acclimatized (some acclimatized plants have been infested by mealybugs). Micropropagated and acclimatized plants leaves were extracted with AcOEt. The metabolomic profile of each extract was analyzed by 1H NMR and each crude extract was tested for antiplasmodial activity. Several multivariate analysis were performed to identify active compounds. Studied factors : age (6, 7, 8 and 9 month), type of plant (micropropagated vs acclimatized) and infection of plants.

I. Introduction The genus Psiadia Jacq. Ex. Willd. belongs to the Asteraceae family and includes more than 60 species, which are well represented in Madagascar and the Mascarene Islands (La Réunion, Mauritius and Rodrigues) (Bosser et al., 1993). Several Psiadia species have been used traditionally to treat various ailments such as expectorant for treatment of bronchitis and asthma, colds and abdominal pains (Sussman, 1980). According to litterature, only a few species of the genus Psiadia have been studied for their chemical composition and pharmacological potential. However, preliminary screenings have displayed for example the antiplasmodial, anticancer and anti-inflammatory potentials of P. arguta (endemic to Mauritius) and P. dentata (endemic to La Réunion) (Jonville et al., 2008, 2010). In order to make a comprehensive study of the genus Psiadia in the Mascarene Islands and to provide scientific basis for furture research, a biological screening has been carried out for 11 species from La Réunion and 5 species from Mauritius. The anticancer, antiplasmodial and anti-inflammatory activities of all plant extracts have been investigated. The active compounds of P. arguta crude extract have been purified by activity-guided isolations. The production of these compounds through the growth of the plant have also been studied by a metabolomic approach.

Vitroplants

Acclimatized plant

Factors studied : Age è No influence Type of plant è No influence Infection è Influence

Multivariate analysis

Five species have been identified for their promising biological activities : P. amygdalina, P. anchusifolia and P. dentata, endemic to La Réunion, and P. arguta and P. lithospermifolia, endemic to Mauritius. The phytochemical investigation of wild P. arguta plants led to isolation and characterization of 16 compounds including 4 new diterpenoids. The production of compounds 3 and 4 appeared to be induced when the young plants are stressed. These compounds might be responsible for the antiplasmodial activity of young infested plants of P. arguta. The evaluation of the antiplasmodial and anticancer activities of the isolated compounds is in progress in order to confirm these results.

Bosser, J., Guého, J., Jeffrey, C., 1993. 109. Composées. In: Flore des Mascareignes. La Réunion, Maurice, Rodrigues., The Sugar Industry Research Institute, Mauritius, L’Institut Français de Recherche Scientifique pour le Développement en Coopération (ORSTOM). ed. Paris, The Royal Botanic Gardens, Kew. Jonville, M.C., Kodja, H., Humeau, L., Fournel, J., De Mol, P., Cao, M., Angenot, L., Frédérich, M., 2008. Screening of medicinal plants from Reunion Island for antimalarial and cytotoxic activity. J. Ethnopharmacol. 120, 382–386. doi:10.1016/j.jep.2008.09.005 Jonville, M.C., Kodja, H., Strasberg, D., Pichette, A., Ollivier, E., Frédérich, M., Angenot, L., Legault, J., 2011. Antiplasmodial, anti-inflammatory and cytotoxic activities of various plant extracts from the Mascarene Archipelago. J. Ethnopharmacol., Immunomodulators 136, 525–531. doi:10.1016/j.jep.2010.06.013 Sussman, L.K., 1980. Herbal medicine on Mauritius. J. Ethnopharmacol. 2, 259–278. doi:10.1016/S0378-8741(80)81005-1

Keshika Mahadeoa, Isabelle Grondina, Hippolyte Kodjab, Joyce Soulange Govindenc, Sabina Jhaumeer Laullood, Gaëtan Herbettee, Michel Frederichf, Anne Gauvin-Bialeckia, a Laboratoire de Chimie des Substances Naturelles et des Sciences des Aliments, Faculté des Sciences et Technologies, Université de la Réunion, 15 Avenue René Cassin, BP 7151, St Denis Messag Cedex 9, La Réunion 97 715, France.

b UMR Qualisud, Université de La Réunion, BP 7151, 15 avenue René Cassin, 97744 Saint-Denis Cedex 09, La Réunion, France. c Department of Agriculture and Food Science, Faculty of Agriculture, The University of Mauritius, Mauritius.

d Department of Chemistry, Faculty of Science, The University of Mauritius, Mauritius. e Université de Liège, Département de Pharmacie, Centre Interfacultaire de Recherche sur le Médicament (CIRM), Laboratoire de Pharmacognosie, Campus du Sart-Tilman, Quartier hôpital, Avenue Hippocrate, 15 B36 4000 Liège, Belgium.

f Spectropole – Aix-Marseille Université, Campus Scientifique de Saint Jérôme, Boîte 511, 13397 Marseille cedex 20, France

6 months

7 months

8 months 9 months

6 months

7 months

8 months 9 months

Chemical profile (1H NMR)

Extraction (solvent AcOEt)

Figure 2 : PCA of P. arguta micropropagated and acclimatized plants extracts

PC1=49,6%

PC2=2

0,4%

Healthyplants

Infestedplants

N=16samples(R2X(cum)=70,0%)Q2(cum)=43,5%

AcDveInacDve

AnDplasmodialacDvity

II. Biological activities of species of the genus Psiadia

III. Phytochemical investigation of Psiadia arguta

IV. Factors influencing the production of bioactives compounds in P. arguta young plants

V. Conclusion and perspectives References

Evaluation of antiplasmodial activity

HARVEST EXTRACTION BIOLOGICAL ACTIVITIES RESULTS

MICROPROPAGATED AND ACCLIMATIZED PLANT PRODUCTION

EXTRACTION AND ANALYSIS RESULTS

Absence of diterpenes 3

and 4

Presence of diterpenes 3

and 4

BIOGUIDED PURIFICATION OF PSIADIA ARGUTA CRUDE EXTRACT ISOLATED SECONDARY METABOLITES

Structural elucidation : HRMS, NMR (1H, 13C, COSY, HSQC, HMBC, NOESY).

1. 2. 3. 4. 5.

6. 7. 8. 9. 10. 11. 12.

13. 14. 15. 16. Semi-preparative reverse phase HPLC

Silica gel column chromatography

16 pure compounds

Triterpenes Diterpenes

New diterpenes

Silica gel column chromatography

Evaluation of biological activities ⇢  Anticancer ⇢  Antiplasmodial ⇢  Anti-inflammatory

18 fractions

Most active fractions (antiplasmodial) Fractions with major compounds

Crude extract (9g)

Fractionation

Fractionation

P.arguta(Mauri'us)

P. arguta (Mauritius)