Antileishmanial activity of verbascoside: Selective arginase inhibition of intracellular amastigotes of Leishmania (Leishmania) amazonensis with resistance induced by LPS plus IFN-γ

Cinnamic acids derived compounds with antileishmanial activity target Leishmania amazonensis arginase

“…We showed previously that a treatment of promastigotes and intracellular amastigotes with a mixture containing 30% and 70%, respectively, of compounds 5 and 6 obtained from S. cayennensis extract was reverted by ornithine addition. The reversion of L. amazonensis growth in culture previously treated with isolated 6 was also reverted by ornithine in both stages of the parasite . Moreover, the antileishmanial activity of others compounds does not match with previously reported probably due to the fact that the L. amazonensis that we used is a different isolated parasite.…”

“…Moreover, the antileishmanial activity of others compounds does not match with previously reported probably due to the fact that the L. amazonensis that we used is a different isolated parasite. In fact, the parasite used in this study showed an unusual growth in experimental infection in macrophage stimulated by LPS and interferon gamma …”

“…The compounds 1–3 were tested because the antileishmanial activity was previously described against L. amazonensis without elucidating a possible mechanism of action and 5 is an isomer of 6 that is active against L. amazonensis . An interesting result was observed for 5 at 24 hr in comparison with its isomer 6 that is effective only 72 hr after drug treatment .…”

“…The main active constituents identified for S. cayennensis are verbascoside and isoverbascoside, both of which contain a hydroxycinnamic acid moiety in their structure . Verbascoside is a selective parasite arginase inhibitor and was active against promastigotes and amastigotes Synthetics cinnamides containing cinnamic acid moiety were also explored as inhibitors of mammal's arginase . Thus, in this study, we tested five hydroxycinnamic acids derived compounds (Figure ) to verify the inhibition of L. amazonensis arginase.…”

Silver and gold nanoparticles from tannic acid: synthesis, characterization and evaluation of antileishmanial and cytotoxic activities

“…The need for new and more effective treatments in the fight against leishmaniasis comes from the high toxicity of currently applied drugs and the emergence of resistant parasites (Maquiaveli et al 2017, Carneiro et al 2012, Jebali and Kazemi 2013, Vieites et al 2009, Allahverdiyev et al 2011. In this context, in vitro antileishmanial assays were performed with L. amazonensis promastigotes.…”