title: Morphological and physiological changes in Leishmania promastigotes induced by yangambin, a lignan obtained from Ocotea duckei.
abstract: We have previously demonstrated that yangambin, a lignan obtained from Ocotea duckei Vattimo (Lauraceae), shows antileishmanial activity against promastigote forms of Leishmania chagasi and Leishmania amazonensis. The aim of this study was to determine the in vitro effects of yangambin against these parasites using electron and confocal microscopy. L. chagasi and L. amazonensis promastigotes were incubated respectively with 50 μg/mL and 65 μg/mL of pure yangambin and stained with acridine orange. Treated-parasites showed significant alterations in fluorescence emission pattern and cell morphology when compared with control cells, including the appearance of abnormal round-shaped cells, loss of cell motility, nuclear pyknosis, cytoplasm acidification and increased number of acidic vesicular organelles (AVOs), suggesting important physiological changes. Ultrastructural analysis of treated-promatigotes showed characteristics of cell death by apoptosis as well as by autophagy. The presence of parasites exhibiting multiples nuclei suggests that yangambin may also affect the microtubule dynamic in both Leishmania species. Taken together our results show that yangambin is a promising agent against Leishmania.
authors.affiliation: Laboratório de Tecnologia Farmacêutica, Universidade Federal da Paraíba, 58051-970 João Pessoa, Paraíba, Brazil.
authors.forename: Rubens L
authors.initials: RL
authors.lastname: Monte Neto
authors.forename: Louisa M A
authors.initials: LM
authors.lastname: Sousa
authors.forename: Celidarque S
authors.initials: CS
authors.lastname: Dias
authors.forename: José M
authors.initials: JM
authors.lastname: Barbosa Filho
authors.forename: Márcia R
authors.initials: MR
authors.lastname: Oliveira
authors.forename: Regina C B Q
authors.initials: RC
authors.lastname: Figueiredo
mesh_terms: D000165:Acridine Orange; D000818:Animals; D004285:Dogs; D005456:Fluorescent Dyes; D005663:Furans / Q000737:chemistry / Q000494:pharmacology*; D007091:Image Processing, Computer-Assisted; D018314:Leishmania infantum / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D007894:Leishmania mexicana / Q000187:drug effects* / Q000502:physiology / Q000648:ultrastructure; D017705:Lignans / Q000737:chemistry / Q000494:pharmacology*; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D027444:Ocotea / Q000737:chemistry*; D010936:Plant Extracts / Q000737:chemistry / Q000494:pharmacology
chemical_list: D005456:Fluorescent Dyes; D005663:Furans; D017705:Lignans; D010936:Plant Extracts; C082827:epiyangambin; D000165:Acridine Orange