Study of Trypanosoma cruzi epimastigote cell death by NMR-visible mobile lipid analysis

Cell death mechanisms in Trypanosoma cruzi have not been disclosed in detail though different conventional techniques have been used in the classification of parasite-cell death type. Nuclear magnetic resonance (NMR) has successfully been used as a tool to evaluate the onset of apoptosis in a number of higher eukaryote-cell models analysing the ratio of CH2/CH3 integration from the visible mobile lipids (VML). Surprisingly, this versatile non-invasive spectroscopy technique has never been employed with this purpose in T. cruzi. In the present study it is shown that under different parasite death-conditions the ratio CH2/CH3 varied drastically. Thus, T. cruzi epimastigotes in apoptotic conditions increase significantly this ratio while in necrotic as well as in autophagic situations the parasites maintain the VML, CH2/CH3 ratio, in normal values. Additionally, other VML markers commonly used in these studies, such as the change in the region of methylcholine moiety, -N+(CH3)(3), exhibited different particular patterns according to the type of cell death. Our results suggest that the H-1 NMR-VML technique is an adequate tool to discriminate different T. cruzi death pathways.