title: Metabolomics to unveil and understand phenotypic diversity between pathogen populations.
abstract: Leishmaniasis is a debilitating disease caused by the parasite Leishmania. There is extensive clinical polymorphism, including variable responsiveness to treatment. We study Leishmania donovani parasites isolated from visceral leishmaniasis patients in Nepal that responded differently to antimonial treatment due to differing intrinsic drug sensitivity of the parasites. Here, we present a proof-of-principle study in which we applied a metabolomics pipeline specifically developed for L. donovani to characterize the global metabolic differences between antimonial-sensitive and antimonial-resistant L. donovani isolates. Clones of drug-sensitive and drug-resistant parasite isolates from clinical samples were cultured in vitro and harvested for metabolomics analysis. The relative abundance of 340 metabolites was determined by ZIC-HILIC chromatography coupled to LTQ-Orbitrap mass spectrometry. Our measurements cover approximately 20% of the predicted core metabolome of Leishmania and additionally detected a large number of lipids. Drug-sensitive and drug-resistant parasites showed distinct metabolic profiles, and unsupervised clustering and principal component analysis clearly distinguished the two phenotypes. For 100 metabolites, the detected intensity differed more than three-fold between the 2 phenotypes. Many of these were in specific areas of lipid metabolism, suggesting that the membrane composition of the drug-resistant parasites is extensively modified. Untargeted metabolomics has been applied on clinical Leishmania isolates to uncover major metabolic differences between drug-sensitive and drug-resistant isolates. The identified major differences provide novel insights into the mechanisms involved in resistance to antimonial drugs, and facilitate investigations using targeted approaches to unravel the key changes mediating drug resistance.
authors.affiliation: Unit of Molecular Parasitology, Department of Parasitology, Institute of Tropical Medicine, Antwerp, Belgium.
authors.forename: Ruben
authors.initials: R
authors.lastname: t'Kindt
authors.forename: Richard A
authors.initials: RA
authors.lastname: Scheltema
authors.forename: Andris
authors.initials: A
authors.lastname: Jankevics
authors.forename: Kirstyn
authors.initials: K
authors.lastname: Brunker
authors.forename: Suman
authors.initials: S
authors.lastname: Rijal
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Dujardin
authors.forename: Rainer
authors.initials: R
authors.lastname: Breitling
authors.forename: David G
authors.initials: DG
authors.lastname: Watson
authors.forename: Graham H
authors.initials: GH
authors.lastname: Coombs
authors.forename: Saskia
authors.initials: S
authors.lastname: Decuypere
mesh_terms: D000981:Antiprotozoal Agents / Q000494:pharmacology / Q000627:therapeutic use; D044822:Biodiversity; D004351:Drug Resistance; D006801:Humans; D007893:Leishmania donovani / Q000737:chemistry* / Q000187:drug effects / Q000235:genetics / Q000378:metabolism*; D007898:Leishmaniasis, Visceral / Q000188:drug therapy / Q000469:parasitology*; D013058:Mass Spectrometry; D055432:Metabolomics; D010641:Phenotype; D015800:Protozoan Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism
chemical_list: D000981:Antiprotozoal Agents; D015800:Protozoan Proteins