Metabolic alterations in the hamster co-infected with Schistosoma japonicum and Necator americanus Jun-Fang Wu a,b , Elaine Holmes c , Jian Xue d , Shu-Hua Xiao d , Burton H. Singer e , Hui-Ru Tang a , Jürg Utzinger f , Yu-Lan Wang a, * a State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics, Wuhan Center for Magnetic Resonance, Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071, People’s Republic of China b Graduate School of Chinese Academy of Sciences, Beijing 100049, People’s Republic of China c Biomolecular Medicine, Department of Surgery and Cancer, Faculty of Medicine, Imperial College London, Sir Alexander Fleming Building, South Kensington, London SW7 2AZ, UK d National Institute of Parasitic Diseases, Chinese Center for Disease Control and Prevention, Shanghai 200025, People’s Republic of China e Office of Population Research, Princeton University, 245 Wallace Hall, Princeton, NJ 08544, USA f Department of Public Health and Epidemiology, Swiss Tropical Institute, P.O. Box, CH-4002 Basel, Switzerland article info Article history: Received 23 September 2009 Received in revised form 3 November 2009 Accepted 4 November 2009 Keywords: Co-infection Hamster Metabonomics Necator americanus NMR spectroscopy Schistosoma japonicum abstract Co-infection with hookworm and schistosomes is a common phenomenon in sub-Saharan Africa, as well as in parts of South America and southeast Asia. As a first step towards understanding the metabolic response of a hookworm-schistosome co-infection in humans, we investigated the metabolic conse- quences of co-infection in an animal model, using a nuclear magnetic resonance (NMR)-based metabolic profiling technique, combined with multivariate statistical analysis. Urine and serum samples were obtained from hamsters experimentally infected with 250 Necator americanus infective L 3 and 100 Schis- tosoma japonicum cercariae simultaneously. In the co-infection model, similar worm burdens were observed as reported for single infection models, whereas metabolic profiles of co-infection represented a combination of the altered metabolite profiles induced by single infections with these two parasites. Consistent differences in metabolic profiles between the co-infected and non-infected control hamsters were observed from 4 weeks p.i. onwards. The predominant metabolic alterations in co-infected ham- sters consisted of depletion of amino acids, tricarboxylic acid cycle intermediates (e.g. citrate and succi- nate) and glucose. Moreover, alterations of a series of gut microbial-related metabolites, such as decreased levels of hippurate, 3-hydroxyphenylpropionic acid, 4-hydroxyphenylpropionic acid and tri- methylamine-N-oxide, and increased concentrations of 4-cresol glucuronide and phenylacetylglycine were associated with co-infection. Our results provide a first step towards understanding the metabolic response of an animal host to multiple parasitic infections. Ó 2009 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved. 1. Introduction Polyparasitism is the co-occurrence of two or more parasite species in the same organism. This phenomenon is common in regions where different parasites co-exist at high frequencies (Pet- ney and Andrews, 1998). For example, a considerable proportion of people have been found to be concurrently infected with multiple parasite species in rural parts of China (Yu et al., 1994; Steinmann et al., 2008) and across Africa (Raso et al., 2004; McKenzie, 2005). Hookworm and schistosomiasis are among the most frequent co-existing parasitic diseases, mainly in sub-Saharan Africa, as well as in parts of South America and southeast Asia. A significant posi- tive association between Schistosoma mansoni and hookworm was noted in villages in western Côte d’Ivoire and Uganda (Keiser et al., 2002; Raso et al., 2004; Fleming et al., 2006), probably explained by shared transmission routes (Petney and Andrews, 1998). The co-infection rate of these two parasites has been reported to reach approximately 20% in schoolchildren in western Côte d’Ivoire (Raso et al., 2006) and 41% in a region of southeast Brazil (Pullan et al., 2008). A concurrent infection with hookworms and schistosomes has been shown to result in a higher rate of anaemia compared with single infections (Brito et al., 2006). The different types of co-exist- ing parasites can result in synergistic or antagonistic interactions in terms of worm burden within a mammalian host. Positive or negative associations among the pathogenic effects subsequently result in either exacerbated or suppressed clinical manifestations (Keusch and Migasena, 1982; Behnke et al., 2001). For example, a host infected with S. mansoni had the ability to expel a subsequent Trichuris muris infection (Curry et al., 1995), and to inhibit the via- bility of Strongyloides venezuelensis worms (Yoshida et al., 1999). 0020-7519/$36.00 Ó 2009 Australian Society for Parasitology Inc. Published by Elsevier Ltd. All rights reserved. doi:10.1016/j.ijpara.2009.11.003 * Corresponding author. Tel.: +86 27 8719 7143; fax: +86 27 8719 9291. E-mail address: yulan.wang@wipm.ac.cn (Y.-L. Wang). International Journal for Parasitology 40 (2010) 695–703 Contents lists available at ScienceDirect International Journal for Parasitology journal homepage: www.elsevier.com/locate/ijpara