Antileishmanial Activity of Lantana camara L. Leaf Extract in Niosomes

Leishmaniasis is a disease caused by more than 20 Leishmania species and comprise a complex group of clinical manifestations., including Cutaneous leishmaniasis (CL). CLis a neglected tropical disease affecting skin and mucous membranes, with treatment options restricted to a limited number of drugs, many of which are associated with significant toxicity. Lantana camara L. is traditionally used to treat dermatological ailments, with studies suggesting its antileishmanial potential due to triterpenes. Nanotechnology, including niosomes (NIOS), has shown promise in the field of medicine. In this context, this study aimed to evaluate the ethanolic extract of L. camara (LCE) and nanoencapsulated in niosomes (LCE-NIOS) against promastigotes and amastigotes of Leishmania amazonensis, as well their toxic effect on mammalian cells. The chemical composition and immunomodulatory effect of LCE was also evaluated. LCE was obtained by static maceration with ethanol, while nanoencapsulation was performed via lipid film hydration .Cytotoxicity was assessed in BALB/C mouse peritoneal macrophages, while antileishmanial activity was tested against L. amazonensis promastigotes, both using MTT method. The effect against intracellular amastigotes was after Giemsa staining. Nitric oxide (NO) induction was evaluated by Griess assay. Phytochemical analysis of LCE showed high content of terpenes (477.51 mg/g) with low levels of phenolic compounds (34.80 mg/g).Although the selectivity index (SI = 14.33) was lower than that of pure LCE (SI = 30.64), nanoencapsulation (LCE-NIOS) markedly enhanced antileishmanial potency, achieving IC₅₀ values of 0.1431 ± 0.0002 µg/mL for promastigotes and 0.833 ± 0.037 µg/mL for intracellular amastigotes of L. amazonensis, representing approximately a 14-fold improvement over the crude extract. LCE also significantly induced nitric oxide (NO) production in a dose-dependent manner in L. amazonensis-infected macrophages, suggesting a possible immunomodulatory mechanism contributing to parasite clearance. These results highlight the pivotal role of terpenoids in LCE’s antileishmanial activity and demonstrate that nanoencapsulation can substantially enhance its efficacy. Further in vivo studies are warranted to confirm its therapeutic potential.