title: The toxic effects of piperine against Trypanosoma cruzi: ultrastructural alterations and reversible blockage of cytokinesis in epimastigote forms.
abstract: In a previous work, we have investigated the effects of piperine and several of its chemical derivatives on the proliferation of the protozoan parasite Trypanosoma cruzi. It was observed that natural piperine is more active against intracellular amastigotes than axenically grown epimastigotes with IC50 values of 4.91 and 7.36 microM, respectively. Despite its superior trypanocidal activity against the intracellular amastigotes, here, we show that piperine did not enhance microbiocidal characteristics of murine peritoneal macrophages (Mø) based on nitric oxide production. As shown by light and electron microscopy analysis, epimastigotes treated with sublethal concentrations of piperine presented a reversible cell cycle arrestment and become round shaped, with swelling of the mitochondrion matrix and intense intracellular vacuolization with structures displaying complex membrane invaginations. Similar to the effects of exposing epimastigotes to the antitumor and microtubule stabilizer taxol, multiplication of cell organelles such as the flagellum, kinetoplast, and nucleus occurred, but division into daughter cells was impaired. Unlike the effects caused by the anti-microtubular vinca alkaloids vincristine and vinblastine, which also induce cytokinesis arrestment in T. cruzi epimastigotes, piperine did not induce the formation of giant multinucleated cells. The data reinforce the selectivity of the mechanisms of action of piperine against T. cruzi.
authors.affiliation: Laboratório de Glicobiologia, Instituto de Biofísica Carlos Chagas Filho, Centro de Ciências da Saúde, Universidade Federal do Rio de Janeiro, Cidade Universitária, Ilha do Fundão, Rio de Janeiro, RJ 21941-902, Brazil.
authors.forename: Leonardo
authors.initials: L
authors.lastname: Freire-de-Lima
authors.forename: Tatiana Santana
authors.initials: TS
authors.lastname: Ribeiro
authors.forename: Gustavo Miranda
authors.initials: GM
authors.lastname: Rocha
authors.forename: Bruno Alves
authors.initials: BA
authors.lastname: Brandão
authors.forename: Alexandre
authors.initials: A
authors.lastname: Romeiro
authors.forename: Lucia
authors.initials: L
authors.lastname: Mendonça-Previato
authors.forename: José Osvaldo
authors.initials: JO
authors.lastname: Previato
authors.forename: Marco Edilson Freire
authors.initials: ME
authors.lastname: de Lima
authors.forename: Técia Maria Ulisses
authors.initials: TM
authors.lastname: de Carvalho
authors.forename: Norton
authors.initials: N
authors.lastname: Heise
mesh_terms: D000470:Alkaloids / Q000494:pharmacology*; D000818:Animals; D052117:Benzodioxoles / Q000494:pharmacology*; D002478:Cells, Cultured; D048749:Cytokinesis / Q000187:drug effects*; D017737:Macrophages, Peritoneal / Q000187:drug effects / Q000276:immunology / Q000469:parasitology; D051379:Mice; D008807:Mice, Inbred BALB C; D008854:Microscopy, Electron; D009569:Nitric Oxide / Q000096:biosynthesis; D021261:Parasitic Sensitivity Tests; D010880:Piperidines / Q000494:pharmacology*; D053284:Polyunsaturated Alkamides / Q000494:pharmacology*; D014344:Trypanocidal Agents / Q000494:pharmacology*; D014349:Trypanosoma cruzi / Q000187:drug effects* / Q000254:growth & development / Q000648:ultrastructure*
chemical_list: D000470:Alkaloids; D052117:Benzodioxoles; D010880:Piperidines; D053284:Polyunsaturated Alkamides; D014344:Trypanocidal Agents; D009569:Nitric Oxide; C008922:piperine