Pharmacological Studies of Ten Medicinal Plants Used for Analgesic Purposes in Congo Brazzaville
Résumé
The aim of this study was to assess ten plants from the Congolese pharmacopoeia for their analgesic activity as well as their cytotoxicity, in order to validate their traditional use. Thirty-three extracts were obtained in 3 different solvents (Water, Ethanol, DCM) from these ten plants selected after an ethnobotanic survey in the region of the Pool (Congo Brazzaville): Leonotis nepetaefolia (Lamiaceae), Manotes pruinosa (Connaraceae), Spilanthes uliginosa (Asteraceae), Hymenocardia ulmoides (Euphorbiaceae), Celosia trigyna (Amaranthaceae), Cogniauxia podolaena (Cucurbitaceae), Brillantaisia patula (Acanthaceae), Urena lobata (Malvaceae) , Mitracarpus scaber (Rubiaceae), Triumfetta rhomboidea (Tiliaceae). The writhing test (Siegmund Chemical Test) was used for the pharmacological screening. The cytotoxicity of all the extracts was tested on KB (Human epidermoid carcinoma) and Vero (African green monkey kidney) cell lines with taxotere as positive control. A TLC chemical screening of the extracts was carried out to detect the major chemical classes present in the plants. The data of the traditional medicine were confirmed, since eight plants out of ten were active, aqueous and ethanolic extracts being the most active. Moreover, only C. podolaena leaf extracts were cytotoxic (87% of inhibition on KB). This work opens the way for the research of the active molecules from these plants and for their use as leads in the synthesis and the pharmacomodulation of compounds with analgesic potentiality.