Ballota hirsutaessential oil as a potential multitarget agent against Leishmaniaparasite: in vitro and in silico studies

In the present study, we assessed the antioxidant and antileishmanial potential from fresh leaves of Ballota (B.) hirsutaessential oil (EO). The GC–MS analysis of B. hirsutaEO revealed that spathulenol and germacrene D were the main components accounting for 26.03% and 19.64% of the total EO, respectively. B. hirsutaEO possesses moderate antioxidant activity, both in neutralizing DPPH radicals and in inhibiting β-carotene bleaching. In addition, it exhibits both high antileishmanial activity and selectivity towards the promastigote and amastigote forms. Specifically, B. hirsutaEO showed an IC50value of 20.78 µg/mL and 23.62 µg/mL, against the promastigote and amastigote forms of L. infantum, respectively. It also demonstrated an IC50value of 22.39 and 25.76 µg/mL, against the promastigote and amastigote forms of L. major, respectively. However, it exhibited moderate cytotoxicity, with a selectivity index below 10. The investigation of the molecular mechanism of action revealed that B. hirsutaEO inhibited only the sterol pathway, including CYP51 gene expression. Additionally, in silico analysis indicated that the main compounds of B. hirsutaEO, germacrene and spathulenol, exhibited excellent affinity energy against Leishmaniaenzymes trypanothione reductase (TryR) and trypanothione synthase (TryS). This denotes the potential of these compounds as promising agents to control leishmaniasis.