In-Vivo and In-Silico Evidence of Antitrypanocidal Activities of Selected Plants from Asteraceae Family against Trypanosoma brucei brucei

Abstract

The menace of animal African trypanosomiasis (AAT) has increased in sub-Saharan Africa despite countless interventions through chemotherapy and health policies. The study evaluated the in-vivo antitrypanosomal activities of five plant species from the Asteraceae family and further subjected some previously isolated compounds from the active plants to molecular docking on an identified T. brucei target. The extracts of the aerial parts of Tithonia diversifolia, Chromolaena odorata, Aspilia africana, Vernonia glaberrima, and Synedrella nodiflora were subjected to in-vivo antitrypanosomal activity against T. b. brucei-infected mice by monitoring the parasitemia and packed cell volume (PCV) at intervals. Some isolated compounds were docked to a co-crystallized ornithine decarboxylase (ODC) enzyme target, and the binding energies were compared. All the extracts (200-600 mg/kg) caused a significant (p < 0.05) decline in the parasitemia level compared with the untreated group. Both T. diversifolia (200-600 mg/kg) and V. glaberrima (400-600 mg/kg) caused total clearance of the parasite from the bloodstream of infected mice by the 17th day. Similarly, except for S. nodiflora and C. odorata, all other tested extracts restored the PCV of the infected mice to the baseline value (> 40 %). Woodhousin from T. diversifolia and apigenin from V. glaberrima interacted maximally with the ODC of T. b. brucei. The study has established the basis for using the selected plants in the management of AAT in folk medicine and further provided insights into the potential of the plant species to provide new bioactive lead compounds.