Two-Photon NAD(P)H-FLIM reveals unperturbed energy metabolism ofAscaris suumlarvae, in contrast to host macrophages upon artemisinin derivatives exposure

Abstract

AbstractTwo-photon microscopy combined with NAD(P)H fluorescence lifetime imaging (FLIM) provides the potential to decipher NAD(P)H-dependent energy metabolism of living cells and organisms. Soil transmitted helminths are highly prevalent withAscaris lumbricoidesinfecting millions of people in sub-Saharan Africa andAscaris suumbeing prevalent in pigs. The artemisinin derivatives artesunate, artemether and dihydroartemisinin (ARTs) are reported to influence energy metabolism of parasites, tumours and immune cells. Herein, two-photon NADPH-FLIM was applied to investigate the metabolism ofA. suumthird-stage larvae (L3) and porcine macrophages exposed to ARTs. Our data showA. suumL3 and porcine macrophages to exhibit a steady-state energy profile of high aerobic / low anaerobic glycolysis. Exposed to ARTs the macrophages decreased their general metabolic activity, without changing specific metabolic pathways. InA. suumlarvae two-photon NAD(P)H-FLIM revealed two metabolically distinct larval regions exhibiting particularly high DUOX-like activity in the pharynx in contrast to the midgut. The metabolic profile of both regions were, however, unperturbed by ARTs exposure. Taken together, two-photon NAD(P)H-FLIM empowered the study of specific metabolic pathways inAscarislarvae as well as in host macrophages, which is particularly relevant for the mechanistic understanding of drug action on the metabolism of both parasite and host.