Background: Cancer is a significant public health problem worldwide and constitutes the second leading cause of death after cardiovascular disease. This study was thus designed to identify new natural compounds from Malagasy medicinal plants traditionally used to treat cancer. Methods: In silico analyses by molecular docking to model ligand–protein interactions, and by SwissADME and ADMET webservers to establish the pharmacokinetic profile of the four investigated compounds in interaction with the angiogenesis target protein HIF-1α/breast cancer (PDB ID: 3KCX) and human androgen receptor/prostate cancer (PDB ID: 1E3G) were performed. Results: The docking results show that the HIF-1α receptor has the best binding energy when it interacts with compound 1 (1′,4-dihydroxy-2,3′-dimethyl-1,2′-binapthyl-5,5′,8,8′-tetraone: − 8.49 kcal/mol) followed by compound 3 [(E)-5,6-dimethyl-2-(2-methyl-3-(prop-1-enyl)phenyl)-2H-chromene: -8.43 kcal/mol], compound 2 (6′-ethoxy-1′3′-dihydroxy-4,6-dimethyl-1,2′-binaphthyl-2,5′,8,8′-tetraone: − 7.80 kcal/mol) and compound 4 (methyl 10-hydroxy-2,4a,6a,9,12b,14a-hexamethyl-11-oxo-1,2,3,4,4a,5,6,6a,11,12b,13,14,14a,14b-tetradecahydropicene-2-carboxylate: − 7.63 kcal/mol). The receptor 1E3G displayed poor binding affinity energy to all tested compounds with energy value above − 11.99 kcal/mol (co-crystal). Based on the H-bonding interaction, ligands 1 and 2 displayed a good pharmacophore profiles to both protein targets 3KCX and 1E3G. Ligand 3 does not interact with the selected receptors via hydrogen bonds. The pharmacokinetic profile of these phyto-compounds revealed that they are orally active and safe. They were isolated and their chemical structures were elucidated previously by our team using chromatographic and spectroscopic techniques (LC/MS/NMR). Conclusions: The ligands 1 and 2 can be considered as hits since in addition to their thermodynamic stability with the receptors; they presented a good pharmacokinetic profile and could thus be useful as an alternative therapy in breast and prostate cancer. This study offers a strong potential in developing new, cost-effective, and safe plant-based natural drugs against cancer.

Discovery Phytomedicine is a peer reviewed, open-access journal dedicated to attract and disseminate novel and experimental innovations with a focus on pharmacology, toxicology and clinical studies of natural products.

Background. Sickle cell disease or drepanocytosis is the most known hemoglobin abnormality in the world. Recently, many medicinal plants used in the management of sickle cell disease in African traditional medicine have shown in vitro antisickling activity. Objective. This research study aims to document some Congolese plant species used in the management of sickle cell disease in Kikwit city and investigate their pharmacological property in vitro. Methods. A cross‐sectional survey was done from June 2015 to March 2016 among 26 traditional healers in Kikwit city, Democratic Republic of Congo. Emmel test was used to assess in vitro antisickling activity. Habitat, morphological, biological types, phytogeographical distribution, local names, and used parts of these plant species were also determined. Results. Obtained results show that 23 plant species belonging to 16 families are used. The leaves represent the most used part (70%). Antisickling investigation showed that aqueous extracts of 18 plants (78%) exhibit a change in the shape of a sickle cell into a normal one with a normalized rate of at least 70%, confirming the in vivo effect observed by traditional healers when used as herbal medicine traditionally in the management of sickle cell disease. The evaluation of perimeter, surface, and radius of untreated and treated sickle red blood cells showed a significant difference (p < 0.05) as modification indicators of the red blood cell shape. Alchornea cordifolia, Alternanthera bettzickiana, Annona senegalensis, Dissotis brazzae, Hypoxis angustifolia, and Justicia secunda presented a very high antisickling activity with normalization >70%. Otherwise, Dissotis brazzae was the most active plant with a minimal concentration of normalization (MCN) of 11 μg/mL and a maximal normalization rate (NRmax) of 86%. Conclusion. Almost 80% of the plants studied showed interesting antisickling activity and justified their use in traditional medicine. The isolation of the molecules responsible for the biological activity of the most active plants and the determination of their chemical structures is under investigation.

In accordance with statistics from the World Health Organization, nearly 80% of populations depend on traditional medicine for primary health care. In order to scientifically validate the phyto-therapeutic wealth of the Democratic Republic of the Congo, three plants were chosen namely: Afromomum alboviolaceum , Annona senegalensis and Mondia whitei . The objective of our study was to assess the antisickling, antioxidant and antibacterial activities of the ethanolic extracts and the dichloromethane fractions of these three plants. Sickle cell blood was supplied from Centre de Médecine Mixte and Anémie SS of Yolo Sud, Kinshasa. Three bacterial strains were used including Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 8739 and Pseudomonas aeroginosa ATCC 9027. The ethanolic extracts of A. alboviolaceum and A. senegalensis and dichloromethane fractions of A. alboviolaceum and M. whitei showed IC50 values < 100 μg/mL in the ABTS test. Only the dichloromethane fraction of A. senengalensis showed an IC ₅₀ value of less than 100 μg/mL for the DPPH test. The inhibitory concentration 50 (IC ₅₀ ) values obtained from the ABTS test are lower than those of the DPPH test. All tested extracts possess a high antisickling activity and only soluble dichloromethane extracts are active vis-à-vis Staphylococcus aureus (MIC = 31.5 μg/mL). These results constitute a scientific evidence validating the use of these three medicinal plants for the management of sickle-cell anemia in the Democratic Republic of the Congo.

To validate scientifically the traditional use of Salacia leptoclada Tul. (Celastraceae) (S. leptoclada) and to isolate and elucidate the structure of the biologically active compound. Bioassay-guided fractionation of the acetonic extract of the stem barks of S. leptoclada was carried out by a combination of chromatography technique and biological experiments in viro using Plasmodium falciparum and P388 leukemia cell lines as models. The structure of the biologically active pure compound was elucidated by 1D and 2D NMR spectroscopy and mass spectrometry. Biological screening of S. leptoclada extracts resulted in the isolation of a pentacyclic triterpenic quinone methide. The pure compound exhibited both in vitro a cytotoxic effect on murine P388 leukemia cells with IC50 value of (0.041±0.020) μg/mL and an antiplasmodial activity against the chloroquine-resistant strain FC29 of Plasmodium falciparum with an IC50 value of (0.052±0.030) μg/mL. Despite this interesting anti-malarial property of the lead compound, the therapeutic index was weak (0.788). In the best of our knowledge, the quinone methide pentacyclic triterpenoid derivative compound is reported for the first time in S. leptoclada. The results suggest that furthers studies involving antineoplastic activity is needed for the development of this lead compound as anticancer drug.