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Inhibitory Effect of Silver Nanoparticles on Trypanothione Reductase Activity and Leishmania infantum Proliferation.

ABSTRACT: In Leishmania the glutathione/glutathione reductase eukaryotic redox sys-tem is replaced by the unique trypanothione/trypanothione reductase (TR) system. In vitro, silver is a more effective TR inhibitor than antimony, the first line drug against leishmaniasis in most endemic countries, and its mechanism of inhibition is similar to that of Sb(III). In particular, silver binds with high affinity to the catalytic triad Cys52, Cys57, and His461', thereby inhibiting TR. Here, Ag(0) activity was tested on the promastigote and amastigote stages of Leishmania infantum using a drug-delivery system consisting in Ag(0) nanoparticles encapsulated by ferritin molecules (PfFt-AgNPs). These were able to induce an antiproliferative effect on the parasites at metal concentrations lower than those used with antimony.

SUBMITTER: Baiocco P

PROVIDER: S-EPMC4017975 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature

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Inhibitory Effect of Silver Nanoparticles on Trypanothione Reductase Activity and Leishmania infantum Proliferation.

Baiocco Paola P Ilari Andrea A Ceci Pierpaolo P Orsini Stefania S Gramiccia Marina M Di Muccio Trentina T Colotti Gianni G

ACS medicinal chemistry letters 20101229 3

In Leishmania the glutathione/glutathione reductase eukaryotic redox sys-tem is replaced by the unique trypanothione/trypanothione reductase (TR) system. In vitro, silver is a more effective TR inhibitor than antimony, the first line drug against leishmaniasis in most endemic countries, and its mechanism of inhibition is similar to that of Sb(III). In particular, silver binds with high affinity to the catalytic triad Cys52, Cys57, and His461', thereby inhibiting TR. Here, Ag(0) activity was test ...[more]

PMID: 24900299

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