Antiprotozoal Activity of Artemisia vulgaris and Berberis vulgaris Against Leishmania major and Trichomonas vaginalis

Leishmania major and Trichomonas vaginalis infections pose a significant global health burden, while current treatments are limited by toxicity, resistance, and restricted accessibility. This study aimed to evaluate the in vitro and ex vivo antileishmanial effects of Artemisia vulgaris and Berberis vulgaris extracts against L. major, as well as their in vitro antitrichomonal activity against T. vaginalis trophozoites. Ethanolic extracts of A. vulgaris and B. vulgaris were tested against L. major promastigotes, intracellular amastigotes, and T. vaginalis trophozoites. Parasite viability was determined by CellTiter-Glo®, microscopy, and rescue–transformation assays, and selectivity indices (SI) were calculated. Amphotericin B and metronidazole served as reference drugs. Both extracts exhibited low cytotoxicity in THP-1 macrophages (A. vulgaris CC₅₀ = 465.2 µg/mL; B. vulgaris = 357.7 µg/mL). Against L. major, B. vulgaris showed greater potency (IC₅₀ = 76.8 µg/mL; SI = 4.7 for amastigotes) than A. vulgaris (IC₅₀ = 179.7 µg/mL; SI = 2.6). Both extracts reduced intracellular parasite burden in a dose-dependent manner, achieving complete clearance at non-cytotoxic concentrations (≥ 300 µg/mL). In T. vaginalis, the extracts induced concentration-dependent inhibition, with IC₅₀ values of 68.9 µg/mL (B. vulgaris, SI = 5.2) and 104.4 µg/mL (A. vulgaris, SI = 4.5). Both extracts exhibited selective, dose-dependent antiprotozoal activity, with B. vulgaris showing superior efficacy, particularly against intracellular L. major and T. vaginalis. These results highlight their potential as natural antiprotozoal sources, warranting further studies on active constituents, mechanisms, and in vivo efficacy.