Ethnobotanical survey and biological activities of plants used for cancer treatment in traditional Senegalese medicine

Female breast cancer is known to be one of the leading causes of death in Senegal. In Senegal, the absence of a national cancer control program, the lack of specialized infrastructure and qualified human resources and the exorbitant cost of care have contributed to the extensive use of traditional medecine, particularly in rural areas. This study aims to inventory the medicinal plants used by these healers and to assess the cytotoxic and antioxidant activities of the most widely used one. Data on healers and their use practices and information on plants were collected through the administration of a structured questionnaire. Based on their citation frequencies during the survey, Antiaris Africana Engler, Hymenocardia Acida Tul. and Halouf Halal (local name) were selected for chemical and biological studies. Their hydroalcoholic extracts were analyzed in terms of antioxidant capacity and cytotoxic effects, again, in the human cancer cell line. The study revealed a total of 65 medicinal plants belonging to 35 different families. The plant parts used by traditional healers are leaves (63.89%), roots (11.11%), bark (15.28%), fruits (2.78%), and others (6.94%). Generally, herbal medicine is prepared as a powder and mixed with water by maceration (55.38%) and administered orally. A. Africana ranked first with a citation frequency of 5.7% and its hydroalcoholic extract had the highest antioxidant activity in TEAC (6533.64±7 μmol ET/g dry plant) and in ORAC (3745.17±4.8 μmol ET/g dry plant) followed by H. Acida in TEAC (3115.6±145 μmol ET/g dry plant) and in ORAC (4105.29±872 μmol ET/g dry plant). The hydroalcoholic extract of A. Africana exhibited the highest cytotoxic activity in MCF-7 (Human mammary) and THP-1 (Human acute monocytic leukemia cell line) but had low activity against HTC-116 (Human carcinoma colorectal) and A-375 (Human skin malignant melanoma). The percentages of proapoptotic cells were, respectively, 68.85±6.22, 58.1±1.90 and 48.58±1.4%. These results provide scientific support for the traditional use of medicinal plants in cancer treatment and constitute a database for biological screening to isolate cytotoxic plant-based molecules.