Antitrypanosomal Effects of (Lam.) Zepern. & Timler Extracts on African Trypanosomes.

African trypanosomiasis is a disease caused by the parasitic protozoa of the genus. Despite several efforts at chemotherapeutic interventions, the disease poses serious health and economic concerns to humans and livestock of many sub-Saharan African countries. (Lam.) Zepern. & Timler ( LZT) is a plant species of important phytochemical and pharmacological relevance in the subtropical zones of the African continent. However, the mechanisms of its antitrypanosomal effects in African trypanosomes remain to be elucidated. The aim of the study was to determine the effects and mechanisms of action of LZT (root) fractions against . (GUTat 3.1 strain), (D10 strain), (3D 7 strain), Jurkat cells, and Chang liver cells were cultivated to the log phase in their respective media at 37°C. Crude extracts and fractions were prepared from air-dried pulverized plant material of LZT (root) using the modified Kupchan method of solvent partitioning. Half-maximal inhibitory concentrations (IC) were determined through the alamar blue cell viability assay. Effects of fractions on cell death and cell cycle of were determined using flow cytometry. Fluorescence microscopy was used to investigate the effects of fractions on the morphology and distribution of . Antitrypanosomal compounds of fractions were characterized using high-performance liquid chromatography (HPLC) and attenuated total reflectance infrared (ATR-IR) spectroscopy. Methanol, butanol, and dichloromethane fractions were selectively active against with respective IC values of 3.89, 4.02, and 5.70 g/ml. Moreover, methanol, butanol, and dichloromethane fractions significantly induced apoptosis-like cell death with remarkable alteration in the cell cycle of . Furthermore, dichloromethane and methanol fractions altered the morphology, induced aggregation, and altered the ratio of nuclei to kinetoplasts in the parasite. The HPLC chromatograms and ATR-IR spectra of the active fractions suggested the presence of aromatic hydrocarbons with hydroxyl, carbonyl, amine, or amide functional groups. The results suggest that LZT have potential chemotherapeutic effects on African trypanosomes with implications for novel therapeutic interventions in African trypanosomiasis.