Quinolines-1,2,3-triazolylcarboxamides exhibits antiparasitic activity in Trichomonas vaginalis

Increased prevalence of metronidazole-resistant infections has resulted in a search for alternative drugs for the treatment of trichomoniasis. In the present study, we report the evaluation of in vitro activity of three quinolines-1,2,3-triazolylcarboxamides (QTCA-1, QTCA-2 and QTCA-3) against Trichomonas vaginalis, evaluation of cytotoxicity in CHO cells and expression of genes related to hydrogenosome by real time PCR. Nine concentrations of these compounds were analyzed for in vitro activity against ATCC 30236 isolate of T. vaginalis. QTCA-2 reported a cytotoxic effect against 100% of T. vaginalis trophozoites at a final concentration of 80 μM with an IC₅₀ of 50 μM. The kinetic growth curve of trophozoites indicated that QTCA-2 reduced the growth by 70% at a concentration of 80 μM after an exposure of 12 h, and induced complete parasite death at 24 h. QTCA-2 induced less than 30% of cytotoxicity in CHO-K1 cells at 80 μM and data showed this concentration and lower ones had no significant cytotoxic effect when compared to the control. There was no significant difference in gene expression (pyruvate-ferredoxin oxidoreductase A and B; Malic enzyme D; Hydrogenase; β-tubulin) when compared to control and MTZ. Further in silico analysis showed that QTCA-2 had significant binding free energy with T. vaginalis lactate dehydrogenase (−9.3 kcal/mol), purine nucleoside phosphorylase (−9.1 kcal/mol) and triosephosphate isomerase (−7.3 kcal/mol). The present study offers new perspectives for exploring the potential of this class of molecules as an additional option for the treatment of trichomoniasis.