CONICET | Buscador de Institutos y Recursos Humanos

Trypanosoma cruzi, the etiological agent of Chagas disease, has a metabolism largely based on the consumption of glucose and proline. Additionally, this amino acid is involved in differentiation processes, cellular invasion and resistance to several stresses as oxidative, metabolic and osmotic. We have previously identified the proline permease TcAAAP069 in T. cruzi and we showed the effect of inhibition and/or blockage of proline transporter TcAAAP069 on parasite survival. Crystal violet (CV) was used for several years as a blood additive for prevention of transfusion transmitted Chagas disease and the protein synthesis inhibition observed by CV could be due to inhibition of amino acid uptake. In this work, we demonstrated that CV enters at least in part through the proline permease TcAAAP069. CV inhibited proline transport and parasites overexpressing proline transporter were more sensitive to its trypanocidal action. The protective effect of proline in oxidative stress situations led to a 3-fold increase resistance when proline was added to the medium along with CV. In order to obtain other drugs that might have similar effects to CV, we performed a similarity-based virtual screening, using the CV as query and different drug databases. So far, two of the obtained compounds proved to be effective as proline transport inhibitors that also had trypanocidal effect. Another drug obtained with this strategy inhibited TcAAAP069 activity but lacked trypanocidal effect. Taken together, these results show that it is possible to obtain new trypanocidal compounds by drug repositioning using CV as a reference. Drug repositioning is one of the recommended strategies by the World Health Organization to fight neglecteddiseases, like Chagas disease, because costs and development time are significantly reduced for its application in therapy.