Trypanosoma cruzi: Insights into naphthoquinone effects on growth and proteinase activity

Abstract

In this study we compared the effects of naphthoquinones (α-lapachone, β-lapachone, nor-β-lapachone and Epoxy-α-lap) on growth of Trypanosoma cruzi epimastigotes forms, and on viability of VERO cells. In addition we also experimentally analyzed the most active compounds inhibitory profile against T. cruzi serine- and cysteine-proteinases activity and theoretically evaluated them against cruzain, the major T. cruzi cysteine proteinase by using a molecular docking approach. Our results confirmed β-lapachone and Epoxy-α-lap with a high trypanocidal activity in contrast to α-lapachone and nor-β-lapachone whereas Epoxy-α-lap presented the safest toxicity profile against VERO cells. Interestingly the evaluation of the active compounds effects against T. cruzi cysteine- and serine-proteinases activities revealed different targets for these molecules. β-Lapachone is able to inhibit the cysteine-proteinase activity of T. cruzi proteic whole extract and of cruzain, similar to E-64, a classical cysteine-proteinase inhibitor. Differently, Epoxy-α-lap inhibited the T. cruzi serine-proteinase activity, similar to PMSF, a classical serine-proteinase inhibitor. In agreement to these biological profiles in the enzymatic assays, our theoretical analysis showed that E-64 and β-lapachone interact with the cruzain specific S2 pocket and active site whereas Epoxy-α-lap showed no important interactions. Overall, our results infer that β-lapachone and Epoxy-α-lap compounds may inhibit T. cruzi epimastigotes growth by affecting T. cruzi different proteinases. Thus the present data shows the potential of these compounds as prototype of protease inhibitors on drug design studies for developing new antichagasic compounds.

Epoxy-α-Lapachone Has In Vitro and In Vivo Anti-Leishmania (Leishmania) amazonensis Effects and Inhibits Serine Proteinase Activity in This Parasite

“…The results presented show that both epoxy-␣-lapachone and Glucantime had effects in the reduction of paw lesions in the treated BALB/c mice. These results, in association with the previous data on the low toxicity of epoxy-␣-lapachone for mammalian cells (15,17), are strong indicators of the potential use of this compound in the treatment of leishmaniasis. Possibly the effects of epoxy-␣-lapachone in the control of lesions in mice are due to multifactorial actions on parasite physiology.…”

Why strategies to control Leishmania spp. multiplication based on the use of proteinase inhibitors should consider multiple targets and not only a single enzyme

“…[18,[30][31][32][33][34] and Trypanosoma cruzi [35][36][37] and their importance in host-parasite interactions for over a decade. Collectively, these manuscripts make a relevant contribution to the search for proteinases that could serve as targets for developing future leishmaniasis treatments.…”

Affinity-Based Methods for the Separation of Parasite Proteins

“…In this study, chromatography was useful for assessing the effects ofLapachone naphthoquinones on a 60 kDa cysteine-protease activity present in T. cruzi. The results demonstrated the potential of this protease inhibitor as a new antichagasic compound (Bourguignon et al, 2011). Another example of a cysteine-protease isolated by inhibitor affinity chromatography in parasites was described for Plasmodium falciparum.…”