Mechanism of Amphotericin B Resistance in Leishmania donovani Promastigotes
AUTOR(ES)
Mbongo, Nicolas
FONTE
American Society for Microbiology
RESUMO
Amphotericin B (AmB)-resistant Leishmania donovani promastigotes were selected by increasing drug pressure, and their biological features were compared with those of the wild-type parent strain. The 50% inhibitory concentration for resistant cells was 20 times higher than that for the wild-type. Resistance was stable after more than 40 passages in drug-free medium, and resistant promastigotes were infective to macrophages in vitro but lost their virulence in vivo. They had 2.5 times longer generation time, decreased AmB uptake, and increased AmB efflux in comparison to the wild type. Fluorescence measurement with a specific plasma membrane probe, 1-[4-(trimethylammonio)-1,6-diphenylhexa]-1,3,5-triene, showed increased membrane fluidity in drug-resistant promastigotes. Analysis of lipid composition showed that in resistant cells saturated fatty acids were prevalent, with stearic acid as the major fatty acid, and the major sterol was an ergosterol precursor, the cholesta-5, 7, 24-trien-3β-ol and not ergosterol as in the AmB-sensitive strain.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=105413Documentos Relacionados
- In Vitro Reversion of Amphotericin B Resistance in Leishmania donovani by Poloxamer 188
- Oxidant-mediated damage of Leishmania donovani promastigotes.
- Interaction of Leishmania donovani Promastigotes with Human Phagocytes
- pH homeostasis in Leishmania donovani amastigotes and promastigotes.
- Miltefosine Induces Apoptosis-Like Death in Leishmania donovani Promastigotes