Anti-piroplasmic potential of the methanolic Peganum harmala seeds and ethanolic Artemisia absinthium leaf extracts

The available drugs against piroplasmosis are insufficient and faced with several challenges, such as drug-resistant parasites and toxicity to treated animals. Therefore, the discovery of new drug compounds is necessary for the effective control of babesiosis and theileriosis. Methanolic Peganum harmala seed extract (MPHSE) and ethanolic Artemisia absinthium leaf extract (EAALE) have several medicinal properties. In the present study, the growth-inhibition effects of MPHSE and EAALE were evaluated in vitro and in vivo. The half-maximal inhibitory concentration (IC50) values for MPHSE against Babesia bovis, B. bigemina, B. divergens, B. caballi, and Theileria equi were 24.9 ± 1.2, 77.1 ± 2.3, 61.1 ± 2.9, 80.8 ± 4.1, and 11.3 ± 2.1 μg/mL, respectively. EAALE exhibited IC50 values of 43.3 ± 3.1, 39.2 ± 2.7, 38.5 ±3.7, 50.3 ± 2.1, and 28.2 ± 2.1 μg/mL against B. bovis, B. bigemina, B. divergens, B. caballi, and T. equi, respectively. The toxicity assay on Madin–Darby bovine kidney (MDBK), mouse embryonic fibroblast (NIH/3T3), and human foreskin fibroblast (HFF) cell lines showed that MPHSE affected the viability of MDBK, NIH/3T3, and HFF cell lines with half maximum effective concentration (EC50) values of 611.7± 10.9, 870 ± 22, and ˃1500 μg/mL, respectively, while EAALE exhibited EC50 values of 340.7 ± 8.5, 736.7 ± 9.3, and 1371.5 ± 17.3 μg/mL against MDBK, NIH/3T3, and HFF cell lines, respectively. In the in vivo experiment, MPHSE and EAALE oral treatments at 150 mg/kg inhibited the growth of Babesia microti in mice by 60% and 55.1%, respectively. These findings suggest that MPHSE and EAALE have the potential to be alternative remedies for treating piroplasmosis.