Multitarget approach to babesiosis therapy: An in vitro study of therapeutic compounds

V. A. Levytska; O. M. Kovalova

doi:10.15421/0226041

V. A. Levytska Podillia State University
O. M. Kovalova Podillia State University

Keywords: Babesia divergens, babesiosis, atovaquone, deferoxamine, flow cytometry, in vitro study, antiparasitic therapy.

Abstract

Babesiosis is a vector-borne parasitic disease caused by intraerythrocytic protozoa of the genus Babesia and represents a significant threat to veterinary health and zoonotic safety. Among the clinically most relevant species in Europe, Babesia divergens is of particular concern due to increasing reports of high prevalence, highlighting the urgent need for novel treatment strategies. In this study, we evaluated the in vitro antiparasitic activity of two compounds with distinct mechanisms of action: atovaquone, a well-established inhibitor of the mitochondrial bc 1 complex, and deferoxamine, a trivalent iron chelator with the potential to disrupt essential intracellular metabolic processes of the parasite. B. divergens was cultivated in bovine erythrocytes, and parasite growth was quantitatively assessed using DNA-specific fluorescent staining combined with flow cytometry. Atovaquone demonstrated potent antiparasitic activity at low concentrations, whereas deferoxamine exhibited moderate but statistically significant inhibitory effects at higher concentrations, likely through interference with iron-dependent metabolic pathways. Notably, combined exposure to atovaquone and deferoxamine at subtherapeutic concentrations resulted in an additive inhibitory effect, achieving over 82% suppression of parasite growth, suggesting complementary modes of action. In addition, this study highlights m e thodological challenges associated with the standardization of in vitro Babesia culture systems in Ukraine, including optimization of cultivation conditions, incubation parameters, staining protocols and analytical strategies. Collectively, these findings support the potential of multitarget approaches that simultaneously disrupt parasite energy metabolism and iron homeostasis and provide a framework for the development of novel antibabesial agents and harmonized in vitro screening methodologies.

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