Fatty Acid Oxidation Is Essential for Egg Production by the Parasitic Flatworm Schistosoma mansoni

Trudeau Institute, Saranac Lake, New York, United States of America.
PLoS Pathogens (Impact Factor: 7.56). 10/2012; 8(10):e1002996. DOI: 10.1371/journal.ppat.1002996
Source: PubMed


Author Summary
Schistosomes are parasitic worms that are the cause of the Neglected Tropical Disease schistosomiasis. Female schistosomes mated with males produce eggs, which either pass out of the host's body for transmission of the infection, or become trapped in host tissues, where they induce inflammation that contributes to disease symptoms. It has been assumed that egg production is a bioenergetically-demanding process fuelled by glucose metabolism. However, we have discovered that egg production is blocked by inhibition of fatty acid oxidation (FAO), the process through which FA are utilized within mitochondria to fuel the tricarboxylic acid cycle and thereby produce substrates for ATP synthesis through oxidative phosphorylation. Consistent with a role for FAO in egg production, fecund females have extensive fat stores, in the form of lipid droplets, whereas virgin adult females have little or no fat reserves. Moreover, fecund females placed into tissue culture exhaust their fat reserves and cease to be able to produce eggs. Since schistosomes cannot produce their own FA, our data point to the acquisition of FA from the host as a key process necessary for egg production. Our findings point to the importance of regulated lipid stores and FAO for egg production by schistosomes.

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Available from: Bart Everts, Jul 30, 2014
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    • "There are significantly fewer LDs in virgin females, and in previously fecund females that have ceased to produce eggs as a result of being cultured (Huang et al., 2012). Moreover, mitochondrial oxygen consumption declines greatly as female schistosomes are maintained in tissue culture medium (Huang et al., 2012). Thus, there are dynamic and kinetically coupled changes in LD and mitochondrial oxygen consumption that are related to "
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