PubMed

Related Articles Synthesis of multi-omic data and community metabolic models reveals insights into the role of hydrogen sulfide in colon cancer. Methods. 2018 Apr 25;: Authors: Hale VL, Jeraldo P, Mundy M, Yao J, Keeney G, Scott N, Heidi Cheek E, Davidson J, Green M, Martinez C, Lehman J, Pettry C, Reed E, Lyke K, White BA, Diener C, Resendis-Antonio O, Gransee J, Dutta T, Petterson XM, Boardman L, Larson D, Nelson H, Chia N Abstract Multi-omic data and genome-scale microbial metabolic models have allowed us to examine microbial communities, community function, and interactions in ways that were not available to us historically. Now, one of our biggest challenges is determining how to integrate data and maximize data potential. Our study demonstrates one way in which to test a hypothesis by combining multi-omic data and community metabolic models. Specifically, we assess hydrogen sulfide production in colorectal cancer based on stool, mucosa, and tissue samples collected on and off the tumor site within the same individuals. 16S rRNA microbial community and abundance data were used to select and inform the metabolic models. We then used MICOM, an open source platform, to track the metabolic flux of hydrogen sulfide through a defined microbial community that either represented on-tumor or off-tumor sample communities. We also performed targeted and untargeted metabolomics, and used the former to quantitatively evaluate our model predictions. A deeper look at the models identified several unexpected but feasible reactions, microbes, and microbial interactions involved in hydrogen sulfide production for which our 16S and metabolomic data could not account. These results will guide future in vitro, in vivo, and in silico tests to establish why hydrogen sulfide production is increased in tumor tissue. PMID: 29704665 [PubMed - as supplied by publisher]

Related Articles Enhancement of mitochondrial biogenesis and paradoxical inhibition of lactate dehydrogenase mediated by 14-3-3η in oncocytomas. J Pathol. 2018 Apr 27;: Authors: Feng J, Zhang Q, Li C, Zhou Y, Zhao S, Hong L, Song Q, Yu S, Hu C, Wang H, Mao C, Shepard MJ, Hao S, Dominah G, Sun M, Wan H, Park DM, Gilbert MR, Xu G, Zhuang Z, Zhang Y Abstract Oncocytomas represent a subset of benign pituitary adenomas that are characterized by significant mitochondrial hyperplasia. Mitochondria are key organelles for energy generation and metabolic intermediate production for biosynthesis in tumor cells, so understanding the mechanism underlying mitochondrial biogenesis and its impact on cellular metabolism in oncocytoma is imperative. Here we studied surgically resected pituitary oncocytomas using multi-omic analyses. Whole-exome sequencing did not detect any nuclear mutations but identified several somatic mutations of mitochondrial DNA (mtDNA), and dysfunctional respiratory complex I. Metabolomic analysis suggested that oxidative phosphorylation was reduced within individual mitochondrion and that there was no reciprocal increase in glycolytic activity. Interestingly, we found a reduction in cellular lactate and reduced expression of lactate dehydrogenase A (LDHA), which contributed to mitochondrial biogenesis in an in vitro cell model. Of note, the hypoxia-response signaling pathway was not up-regulated in pituitary oncocytomas thereby failing to enhance glycolysis. Proteomic analysis identified that 14-3-3η was exclusively overexpressed in oncocytomas and that 14-3-3η was capable of inhibiting glycolysis, leading to mitochondrial biogenesis in the presence of rotenone. Particularly, 14-3-3η inhibited LDHA by direct interaction in the setting of complex I dysfunction, highlighting the role of 14-3-3η overexpression and inefficient oxidative phosphorylation in oncocytoma mitochondrial biogenesis. These findings deepen our understanding of the metabolic changes that occur within oncocytomas and shine a light on the mechanism of mitochondrial biogenesis, providing a novel perspective of metabolic adaption in tumor cells. PMID: 29704241 [PubMed - as supplied by publisher]

Related Articles Relationships between digestive efficiency and metabolomic profiles of serum and intestinal contents in chickens. Sci Rep. 2018 Apr 27;8(1):6678 Authors: Beauclercq S, Nadal-Desbarats L, Hennequet-Antier C, Gabriel I, Tesseraud S, Calenge F, Le Bihan-Duval E, Mignon-Grasteau S Abstract The increasing cost of conventional feedstuffs has bolstered interest in genetic selection for digestive efficiency (DE), a component of feed efficiency, assessed by apparent metabolisable energy corrected to zero nitrogen retention (AMEn). However, its measurement is time-consuming and constraining, and its relationship with metabolic efficiency poorly understood. To simplify selection for this trait, we searched for indirect metabolic biomarkers through an analysis of the serum metabolome using nuclear magnetic resonance (1H NMR). A partial least squares (PLS) model including six amino acids and two derivatives from butyrate predicted 59% of AMEn variability. Moreover, to increase our knowledge of the molecular mechanisms controlling DE, we investigated 1H NMR metabolomes of ileal, caecal, and serum contents by fitting canonical sparse PLS. This analysis revealed strong associations between metabolites and DE. Models based on the ileal, caecal, and serum metabolome respectively explained 77%, 78%, and 74% of the variability of AMEn and its constitutive components (utilisation of starch, lipids, and nitrogen). In our conditions, the metabolites presenting the strongest associations with AMEn were proline in the serum, fumarate in the ileum and glucose in caeca. This study shows that serum metabolomics offers new opportunities to predict chicken DE. PMID: 29703927 [PubMed - in process]

Related Articles An Innovative Approach for The Integration of Proteomics and Metabolomics Data In Severe Septic Shock Patients Stratified for Mortality. Sci Rep. 2018 Apr 27;8(1):6681 Authors: Cambiaghi A, Díaz R, Martinez JB, Odena A, Brunelli L, Caironi P, Masson S, Baselli G, Ristagno G, Gattinoni L, de Oliveira E, Pastorelli R, Ferrario M Abstract In this work, we examined plasma metabolome, proteome and clinical features in patients with severe septic shock enrolled in the multicenter ALBIOS study. The objective was to identify changes in the levels of metabolites involved in septic shock progression and to integrate this information with the variation occurring in proteins and clinical data. Mass spectrometry-based targeted metabolomics and untargeted proteomics allowed us to quantify absolute metabolites concentration and relative proteins abundance. We computed the ratio D7/D1 to take into account their variation from day 1 (D1) to day 7 (D7) after shock diagnosis. Patients were divided into two groups according to 28-day mortality. Three different elastic net logistic regression models were built: one on metabolites only, one on metabolites and proteins and one to integrate metabolomics and proteomics data with clinical parameters. Linear discriminant analysis and Partial least squares Discriminant Analysis were also implemented. All the obtained models correctly classified the observations in the testing set. By looking at the variable importance (VIP) and the selected features, the integration of metabolomics with proteomics data showed the importance of circulating lipids and coagulation cascade in septic shock progression, thus capturing a further layer of biological information complementary to metabolomics information. PMID: 29703925 [PubMed - in process]

Related Articles Plant hormonomics: multiple phytohormone profiling by targeted metabolomics. Plant Physiol. 2018 Apr 27;: Authors: Šimura J, Antoniadi I, Široká J, Tarkowska D, Strnad M, Ljung K, Novak O Abstract Phytohormones are physiologically important small molecules, which play essential roles in intricate signaling networks that regulate diverse processes in plants. We present a method for the simultaneous targeted profiling of 101 phytohormone-related analytes from minute amounts of fresh plant material (< 20 mg). Rapid and non-selective extraction, fast one-step sample purification, and extremely sensitive ultra-high-performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) enable concurrent quantification of the main phytohormone classes: cytokinins, auxins, brassinosteroids, gibberellins, jasmonates, salicylates, and abscisates. We validated this 'hormonomic' approach in salt-stressed and control Arabidopsis thaliana seedlings, quantifying a total of 43 endogenous compounds in both root and shoot samples. Subsequent multivariate statistical data processing and cross-validation with transcriptomic data highlighted the main hormone metabolites involved in plant adaptation to salt stress. PMID: 29703867 [PubMed - as supplied by publisher]

Related Articles Proteomics and immunohistochemistry identify the expression of α-cardiac myosin heavy chain in the jaw-closing muscles of sooty mangabeys (order Primates). Arch Oral Biol. 2018 Feb 03;: Authors: Wall CE, Holmes M, Soderblom EJ, Taylor AB Abstract OBJECTIVE: The jaw-closing muscles of humans and nonprimate mammals express alpha-cardiac fibers but MyHC α-cardiac has not been identified in the jaw adductors of nonhuman primates. We determined whether MyHC α-cardiac is expressed in the superficial masseter and temporalis muscles of the sooty mangabey (Cercocebus atys), an African Old World monkey that specializes on hard seeds. DESIGN: LC-MS/MS based proteomics was used to identify the presence of MyHC Iα. Immunohistochemistry was used to analyze the composition and distribution of fiber types in the superficial masseter and temporalis muscles of eight C. atys. Serial sections were stained against MyHC α-cardiac (MYH6), as well as MyHC-1 (NOQ7.5.4D), MyHC-2 (MY-32), and MyHC-M (2F4). RESULTS: Proteomics analysis identified the presence of Myosin-6 (MyHC α-cardiac) in both heart atrium and superficial masseter. MyHC α-cardiac was expressed in abundance in the superficial masseter and temporalis muscles of all eight individuals and hybrid fibers were common. CONCLUSIONS: The identification of MyHC α-cardiac in the jaw adductors of sooty mangabeys is a novel finding for nonhuman primates. The abundance of MyHC α-cardiac indicates a fatigue-resistant fiber population characterized by intermediate speed of contraction between pure MyHC-1 and MyHC-2 isoforms. We suggest that α-cardiac fibers may be advantageous to sooty mangabeys, whose feeding behavior includes frequent crushing of relatively large, hard seeds during the power stroke of ingestion. Additional studies comparing jaw-adductor fiber phenotype of hard-object feeding primates and other mammals are needed to explore this relationship further. PMID: 29703519 [PubMed - as supplied by publisher]

Related Articles Next generation microbiological risk assessment-Potential of omics data for hazard characterisation. Int J Food Microbiol. 2018 Apr 12;: Authors: Haddad N, Johnson N, Kathariou S, Métris A, Phister T, Pielaat A, Tassou C, Wells-Bennik MHJ, Zwietering MH Abstract According to the World Health Organization estimates in 2015, 600 million people fall ill every year from contaminated food and 420,000 die. Microbial risk assessment (MRA) was developed as a tool to reduce and prevent risks presented by pathogens and/or their toxins. MRA is organized in four steps to analyse information and assist in both designing appropriate control options and implementation of regulatory decisions and programs. Among the four steps, hazard characterisation is performed to establish the probability and severity of a disease outcome, which is determined as function of the dose of toxin and/or pathogen ingested. This dose-response relationship is subject to both variability and uncertainty. The purpose of this review/opinion article is to discuss how Next Generation Omics can impact hazard characterisation and, more precisely, how it can improve our understanding of variability and limit the uncertainty in the dose-response relation. The expansion of omics tools (e.g. genomics, transcriptomics, proteomics and metabolomics) allows for a better understanding of pathogenicity mechanisms and virulence levels of bacterial strains. Detection and identification of virulence genes, comparative genomics, analyses of mRNA and protein levels and the development of biomarkers can help in building a mechanistic dose-response model to predict disease severity. In this respect, systems biology can help to identify critical system characteristics that confer virulence and explain variability between strains. Despite challenges in the integration of omics into risk assessment, some omics methods have already been used by regulatory agencies for hazard identification. Standardized methods, reproducibility and datasets obtained from realistic conditions remain a challenge, and are needed to improve accuracy of hazard characterisation. When these improvements are realized, they will allow the health authorities and government policy makers to prioritize hazards more accurately and thus refine surveillance programs with the collaboration of all stakeholders of the food chain. PMID: 29703417 [PubMed - as supplied by publisher]

Related Articles 1H NMR-based metabolomics approach to investigating the renal protective effects of Genipin in diabetic rats. Chin J Nat Med. 2018 Apr;16(4):261-270 Authors: Tian JS, Zhao L, Shen XL, Liu H, Qin XM Abstract Diabetic nephropathy is one of the various complications of diabetes mellitus, affecting patients for lifetime. Earlier studies have revealed that genipin can not only improve diabetes, but also induce cytotoxicity. Therefore, it is not clear which effect of genipin on kidneys occurs, when it is used in the treatment of diabetes. In the present study, we performed nuclear magnetic resonance (NMR)-based metabolomics analysis of urine and kidney tissue samples obtained from diabetic rats to explore the change of endogenous metabolites associated with diabetes and concomitant kidney disease. Nine significant differential metabolites that were closely related to renal function were screened. They were mainly related to three metabolic pathways: synthesis and degradation of ketone bodies, glycine, serine and threonine metabolism, and butanoate metabolism, which are involved in methylamine metabolism, energy metabolism and amino acid metabolism. In addition, after the intervention of genipin, the metabolic levels of all the metabolites tended to be normal, indicating a protective effect of genipin on kidneys. Our results may be helpful for understanding the antidiabetic effect of genipin. PMID: 29703326 [PubMed - in process]

17 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: metabolomics These pubmed results were generated on 2018/04/28PubMed comprises more than millions of citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

22 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: metabolomics These pubmed results were generated on 2018/04/27PubMed comprises more than millions of citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

Gut Microbiota-Derived Tryptophan Metabolites Modulate Inflammatory Response in Hepatocytes and Macrophages. Cell Rep. 2018 Apr 24;23(4):1099-1111 Authors: Krishnan S, Ding Y, Saedi N, Choi M, Sridharan GV, Sherr DH, Yarmush ML, Alaniz RC, Jayaraman A, Lee K Abstract The gut microbiota plays a significant role in the progression of fatty liver disease; however, the mediators and their mechanisms remain to be elucidated. Comparing metabolite profile differences between germ-free and conventionally raised mice against differences between mice fed a low- and high-fat diet (HFD), we identified tryptamine and indole-3-acetate (I3A) as metabolites that depend on the microbiota and are depleted under a HFD. Both metabolites reduced fatty-acid- and LPS-stimulated production of pro-inflammatory cytokines in macrophages and inhibited the migration of cells toward a chemokine, with I3A exhibiting greater potency. In hepatocytes, I3A attenuated inflammatory responses under lipid loading and reduced the expression of fatty acid synthase and sterol regulatory element-binding protein-1c. These effects were abrogated in the presence of an aryl-hydrocarbon receptor (AhR) antagonist, indicating that the effects are AhR dependent. Our results suggest that gut microbiota could influence inflammatory responses in the liver through metabolites engaging host receptors. PMID: 29694888 [PubMed - in process]

Correction to ADAP-GC 3.0: Improved Peak Detection and Deconvolution of Co-eluting Metabolites from GC/TOF-MS Data for Metabolomics Studies. Anal Chem. 2018 Apr 25;: Authors: Ni Y, Su M, Qiu Y, Jia W, Du X PMID: 29694022 [PubMed - as supplied by publisher]

Metabolic characterization of serum from mice challenged with Orientia tsutsugamushi-infected mites. New Microbes New Infect. 2018 May;23:70-76 Authors: Chao CC, Ingram BO, Lurchachaiwong W, Ching WM Abstract Scrub typhus is an acute zoonosis caused by the obligate intracellular Gram-negative bacterium Orientia tsutsugamushi. To better understand the host response elicited by natural infection by chigger feeding, ICR mice were infected by Leptotrombidium chiangraiensis (Lc1) chiggers, and the metabolic profiles of their serum were examined over several time points after initiation of feeding. ICR mice were infected by either naive Lc1 chiggers (i.e. not infected by O. tsutsugamushi, NLc1) or O. tsutsugamushi-infected Lc1 chiggers (OLc1). Serum was collected from both groups of mice at 6 hours and 10 days after initiation of feeding. Metabolites were extracted from the serum and analysed by ultra performance liquid chromatography-tandem mass spectrometry. The resulting ion/chromatographic features were matched to a library of chemical standards for identification and quantification. Biochemicals that differed significantly between the experimental groups were identified using Welch's two-sample t tests; p ≤ 0.05 was considered statistically significant. A number of biochemicals linked to immune function were found to be significantly altered between mice infected by the NLc1 and OLc1 chiggers, including itaconate, kynurenine and histamine. Several metabolites linked to energy production were also found to be altered in the animals. In addition lipid and carbohydrate metabolism, bile acid and phospholipid homeostasis, and nucleotide metabolism were also found to be different in these two groups of mice. Markers of stress and food intake were also significantly altered. Global untargeted metabolomic characterization revealed significant differences in the biochemical profiles of mice infected by the NLc1 versus OLc1 chiggers. These findings provide an important platform for further investigation of the host responses associated with chigger-borne O. tsutsugamushi infections. PMID: 29692908 [PubMed]

Metabolic characterization of isocitrate dehydrogenase (IDH) mutant and IDH wildtype gliomaspheres uncovers cell type-specific vulnerabilities. Cancer Metab. 2018;6:4 Authors: Garrett M, Sperry J, Braas D, Yan W, Le TM, Mottahedeh J, Ludwig K, Eskin A, Qin Y, Levy R, Breunig JJ, Pajonk F, Graeber TG, Radu CG, Christofk H, Prins RM, Lai A, Liau LM, Coppola G, Kornblum HI Abstract Background: There is considerable interest in defining the metabolic abnormalities of IDH mutant tumors to exploit for therapy. While most studies have attempted to discern function by using cell lines transduced with exogenous IDH mutant enzyme, in this study, we perform unbiased metabolomics to discover metabolic differences between a cohort of patient-derived IDH1 mutant and IDH wildtype gliomaspheres. Methods: Using both our own microarray and the TCGA datasets, we performed KEGG analysis to define pathways differentially enriched in IDH1 mutant and IDH wildtype cells and tumors. Liquid chromatography coupled to mass spectrometry analysis with labeled glucose and deoxycytidine tracers was used to determine differences in overall cellular metabolism and nucleotide synthesis. Radiation-induced DNA damage and repair capacity was assessed using a comet assay. Differences between endogenous IDH1 mutant metabolism and that of IDH wildtype cells transduced with the IDH1 (R132H) mutation were also investigated. Results: Our KEGG analysis revealed that IDH wildtype cells were enriched for pathways involved in de novo nucleotide synthesis, while IDH1 mutant cells were enriched for pathways involved in DNA repair. LC-MS analysis with fully labeled 13C-glucose revealed distinct labeling patterns between IDH1 mutant and wildtype cells. Additional LC-MS tracing experiments confirmed increased de novo nucleotide synthesis in IDH wildtype cells relative to IDH1 mutant cells. Endogenous IDH1 mutant cultures incurred less DNA damage than IDH wildtype cultures and sustained better overall growth following X-ray radiation. Overexpression of mutant IDH1 in a wildtype line did not reproduce the range of metabolic differences observed in lines expressing endogenous mutations, but resulted in depletion of glutamine and TCA cycle intermediates, an increase in DNA damage following radiation, and a rise in intracellular ROS. Conclusions: These results demonstrate that IDH1 mutant and IDH wildtype cells are easily distinguishable metabolically by analyzing expression profiles and glucose consumption. Our results also highlight important differences in nucleotide synthesis utilization and DNA repair capacity that could be exploited for therapy. Altogether, this study demonstrates that IDH1 mutant gliomas are a distinct subclass of glioma with a less malignant, but also therapy-resistant, metabolic profile that will likely require distinct modes of therapy. PMID: 29692895 [PubMed]

A Vegetal Biopolymer-Based Biostimulant Promoted Root Growth in Melon While Triggering Brassinosteroids and Stress-Related Compounds. Front Plant Sci. 2018;9:472 Authors: Lucini L, Rouphael Y, Cardarelli M, Bonini P, Baffi C, Colla G Abstract Plant biostimulants are receiving great interest for boosting root growth during the first phenological stages of vegetable crops. The present study aimed at elucidating the morphological, physiological, and metabolomic changes occurring in greenhouse melon treated with the biopolymer-based biostimulant Quik-link, containing lateral root promoting peptides, and lignosulphonates. The vegetal-based biopolymer was applied at five rates (0, 0.06, 0.12, 0.24, or 0.48 mL plant-1) as substrate drench. The application of biopolymer-based biostimulant at 0.12 and 0.24 mL plant-1 enhanced dry weight of melon leaves and total biomass by 30.5 and 27.7%, respectively, compared to biopolymer applications at 0.06 mL plant-1 and untreated plants. The root dry biomass, total root length, and surface in biostimulant-treated plants were significantly higher at 0.24 mL plant-1 and to a lesser extent at 0.12 and 0.48 mL plant-1, in comparison to 0.06 mL plant-1 and untreated melon plants. A convoluted biochemical response to the biostimulant treatment was highlighted through UHPLC/QTOF-MS metabolomics, in which brassinosteroids and their interaction with other hormones appeared to play a pivotal role. Root metabolic profile was more markedly altered than leaves, following application of the biopolymer-based biostimulant. Brassinosteroids triggered in roots could have been involved in changes of root development observed after biostimulant application. These hormones, once transported to shoots, could have caused an hormonal imbalance. Indeed, the involvement of abscisic acid, cytokinins, and gibberellin related compounds was observed in leaves following root application of the biopolymer-based biostimulant. Nonetheless, the treatment triggered an accumulation of several metabolites involved in defense mechanisms against biotic and abiotic stresses, such as flavonoids, carotenoids, and glucosinolates, thus potentially improving resistance toward plant stresses. PMID: 29692795 [PubMed]

Deciphering hepatocellular carcinoma through metabolomics: from biomarker discovery to therapy evaluation. Cancer Manag Res. 2018;10:715-734 Authors: Guo W, Tan HY, Wang N, Wang X, Feng Y Abstract Hepatocellular carcinoma (HCC) is the third most common cause of death from cancer, with increasing prevalence worldwide. The mortality rate of HCC is similar to its incidence rate, which reflects its poor prognosis. At present, the diagnosis of HCC is still mostly dependent on invasive biopsy, imaging methods, and serum α-fetoprotein (AFP) testing. Because of the asymptomatic nature of early HCC, biopsy and imaging methods usually detect HCC at the middle-late stages. AFP has limited sensitivity and specificity, as many other nonmalignant liver diseases can also result in a very high serum level of AFP. Therefore, better biomarkers with higher sensitivity and specificity at earlier stages are greatly needed. Since metabolic reprogramming is an essential hallmark of cancer and the liver is the metabolic hub of living systems, it is useful to investigate HCC from a metabolic perspective. As a noninvasive and nondestructive approach, metabolomics provides holistic information on dynamically metabolic responses of living systems to both endogenous and exogenous factors. Therefore, it would be conducive to apply metabolomics in investigating HCC. In this review, we summarize recent metabolomic studies on HCC cellular, animal, and clinicopathologic models with attention to metabolomics as a biomarker in cancer diagnosis. Recent applications of metabolomics with respect to therapeutic and prognostic evaluation of HCC are also covered, with emphasis on the potential of treatment by drugs from natural products. In the last section, the current challenges and trends of future development of metabolomics on HCC are discussed. Overall, metabolomics provides us with novel insight into the diagnosis, prognosis, and therapeutic evaluation of HCC. PMID: 29692630 [PubMed]

22 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: metabolomics These pubmed results were generated on 2018/04/25PubMed comprises more than millions of citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

26 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: metabolomics These pubmed results were generated on 2018/04/24PubMed comprises more than millions of citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

26 new pubmed citations were retrieved for your search. Click on the search hyperlink below to display the complete search results: metabolomics These pubmed results were generated on 2018/04/24PubMed comprises more than millions of citations for biomedical literature from MEDLINE, life science journals, and online books. Citations may include links to full-text content from PubMed Central and publisher web sites.

Related Articles NMR-based metabolic toxicity of low-level Hg exposure to earthworms. Environ Pollut. 2018 Apr 18;239:428-437 Authors: Tang R, Ding C, Dang F, Ma Y, Wang J, Zhang T, Wang X Abstract Mercury is a globally distributed toxicant to aquatic animals and mammals. However, the potential risks of environmental relevant mercury in terrestrial systems remain largely unclear. The metabolic profiles of the earthworm Eisenia fetida after exposure to soil contaminated with mercury at 0.77 ± 0.09 mg/kg for 2 weeks were investigated using a two-dimensional nuclear magnetic resonance-based (1H-13C NMR) metabolomics approach. The results revealed that traditional endpoints (e.g., mortality and weight loss) did not differ significantly after exposure. Although histological examination showed sub-lethal toxicity in the intestine as a result of soil ingestion, the underlying mechanisms were unclear. Metabolite profiles revealed significant decreases in glutamine and 2-hexyl-5-ethyl-3-furansulfonate in the exposed group and remarkable increases in glycine, alanine, glutamate, scyllo-inositol, t-methylhistidine and myo-inositol. More importantly, metabolic network analysis revealed that low mercury in the soil disrupted osmoregulation, amino acid and energy metabolisms in earthworms. A metabolic net link and schematic diagram of mercury-induced responses were proposed to predict earthworm responses after exposure to mercury at environmental relevant concentrations. These results improved the current understanding of the potential toxicity of low mercury in terrestrial systems. PMID: 29679940 [PubMed - as supplied by publisher]