ABSTRACT
Nowadays, the pharmacological therapy for the treatment of Chagas disease is based on two old drugs, benznidazole and nifurtimox, which have restricted efficacy against the chronic phase of the illness. To overcome the lack of efficacy of the traditional drugs (and their considerable toxicity), new molecular targets have been studied as starting points to the discovery of new antichagasic compounds. Among them, polyamine transporter TcPAT12 (also known as TcPOT1.1) represents an interesting macromolecule, since polyamines are essential for Trypanosoma cruzi, the parasite that causes the illness, but it cannot synthesize them de novo. In this investigation we report the results of a combined ligand- and structure-based virtual screening for the discovery of new inhibitors of TcPAT12. Initially we filtered out ZINC and Drugbank databases with similarity and QSAR models and then we submitted the candidates to a validated docking based screening. Four structures were selected and tested in T. cruzi epimastigotes proliferation and two of them, Cisapride and [2-(cyclopentyloxy)phenyl]methanamine showed inhibitory effects. Additionally, we performed transport assays which demonstrated that Cisapride interferes with putrescine uptake in a specific mode.
Subject(s)
Chagas Disease/drug therapy , Cisapride/pharmacology , Protozoan Proteins/antagonists & inhibitors , Putrescine/antagonists & inhibitors , Trypanosoma cruzi/drug effects , Biological Transport/drug effects , Cisapride/therapeutic use , Drug Evaluation, Preclinical/methods , Ligands , Membrane Transport Proteins/drug effects , Molecular Docking Simulation/methods , Molecular Structure , Polyamines/pharmacokinetics , Putrescine/pharmacokinetics , Trypanosoma cruzi/metabolismABSTRACT
As part of our search for potential anticonvulsant agents, a set of compounds were designed, synthesized, and evaluated against MES and PTZ tests. Bioisosteric functional group information was used to design a new functionality, sulfamides, that complies with the requirements of the pharmacophore previously defined. Some of the molecules showed a promising anticonvulsant profile as selective anti-MES drugs, being active at low concentrations (30mg/kg). The biological data were confirmed in Phase II of the Anticonvulsant Drug Development Program of the National Institute of Health.