Natural treatments: lactoferrin exerts antigiardicidal effects through stress and critical morphological defects

FRONTERA L; LANFREDI-RANGEL, A; TOUZ MC

Congreso; Reunión Conjunta de Sociedades de Biociencias.; 2017

Understanding how parasites respond to mechanisms of cellularstress is necessary to identify essential processes on their life. Giardialamblia is a protozoa parasite that is the most common causeof non-viral non-bacterial diarrheal disease world-wide. Despite theeffectiveness of metronidazole, a major antigiardial drug, its strongside effects has been matter of concern. Consequently, the searchfor natural treatments is important for the control of the illness. Glycoproteinbovine lactoferrin (bLF) and its peptide lactoferricin (bLFcin),have exhibited antimicrobial activity in Giardia. However, there is littleevidence of the underlying mechanisms for their effect. Thus, ourgoal was to understand how these molecules are internalized andhow their microbicide mechanism beyond cell death takes place.To address this point, we performed uptake experiments and differentfluorescence and electron microscopy techniques. Our resultsshowed that both molecules are internalized by receptor-mediatedendocytosis and are localized in the endo-lysosomal compartments.By transmission and scanning electron microscopy, we observedthat both bLF and bLFcin produce morphological changes correlatedwith the trigger of ER stress. Moreover, trophozoite treatmentleads to a partial encystation process probably as a consequenceof the general stress induced in the cell. Our findings reinforce theknowledge of a safety use of lactoferrin as treatment for giardiasis.